The author(s) shown below used Federal funding provided by the U.S. 

Department of Justice to prepare the following resource: 

Document Title:

Author(s):

Development of a Real-time PCR Assay 

for the Detection of Blood, Saliva, and 

Semen

Cynthia B. Zeller, Ph.D. 

Document Number: 251633

Date Received: April 2018

Award Number: 2008-DN-BX-K137

This resource has not been published by the U.S. Department of 

Justice. This resource is being made publically available through the 

Office of Justice Programs’ National Criminal Justice Reference 

Service. 

Opinions or points of view expressed are those of the author(s) and 

do not necessarily reflect the official position or policies of the U.S. 

Department of Justice.
1

NATIONAL INSTITUTE OF JUSTICE 

2008-DN-BX-K137 

Development of a Real-time PCR Assay for the Detection of 

Blood, Saliva and Semen

Cynthia Zeller, Ph.D. 

czeller@towson.edu

410-704-2170

EIN: 526002033 

DUNS: 143372741 

Towson University 

College of Graduate Studies and Research 

and 

Fisher College of Science and Mathematics

Department of Chemistry 

Forensic Science Program 

8000 York Rd.

Towson, MD 21252 

PROJECT START DATE: November 1, 2008 

FINAL REPORT

February 28, 2013 

Cynthia B. Zeller, Ph.D 

Principal Investigator
2

ABSTRACT

During the process of forensic DNA genotyping, evidence containing potential DNA 

evidence undergoes serological screening to determine which body fluid, if any, it contains. 

The majority of the DNA genotyping process has under gone automation, leaving a bottleneck 

at the serological analysis stage. This is due in large part to the methods employed to identify 

body fluids. Since most of the commonly used assays test for the presence or function of a

particular protein prevalent in a specific body fluid, these tests cannot be multiplexed and 

therefore can use a fairly large portion of a stain if multiple body fluids need to be identified. 

The purpose of this study was to attempt to develop an assay for the detection of sperm, blood 

and saliva that could be multiplexed, save time and sample and could be dovetailed into the 

current workflow of a forensic DNA laboratory. 

The method of choice for this study was the development of a methylation specific PCR 

assay base on a dual labeled TaqMan® probe. Two assays for the identification of semen were 

generated, each with appropriate tissue specificity, single cell sensitivity in single source 

samples and in mixtures. The thought was that individual assays for the detection of sperm, 

blood and saliva could be multiplexed by utilized different 5’dyes. Unfortunately, this did not 

come to fruition since none of the primer sets tested for the detection of blood and saliva were 

specific enough to be used for identification. Although the ultimate goal of this project was not 

reached, the two assays for the detection of sperm provide a proof of concept for this type of 

assay. With the advent of more information about the epigenome of normal tissues, this type 

of testing could provide a quick, sensitive detection system for multiple body fluids in the 

forensic laboratory.
3

Table of Contents

ABSTRACT ............................................................................................................................. 2

Table of Contents.................................................................................................................. 3

Executive Summary: .............................................................................................................. 4

Synopsis of the problem and purpose of this research:....................................................................4

Research design .............................................................................................................................5

Findings and conclusions................................................................................................................5

Implications for policy and practice.................................................................................................6

Technical Report: .................................................................................................................. 7

Goals of the Project:.......................................................................................................................7

Literature Review:..........................................................................................................................9

Why perform serology testing? ............................................................................................................9

Methods for Body fluid Identification:..................................................................................................9

Role of Methylation of DNA in Gene Expression: ...............................................................................11

Materials and Methods ................................................................................................................14

Bioinformatics.....................................................................................................................................14

Body Fluid Samples.............................................................................................................................16

Bisulfite treatment of DNA .................................................................................................................16

Quantitative PCR.................................................................................................................................16

Results:........................................................................................................................................18

Developmental Pluripotency Antigen 5 (DPPA5):...............................................................................18

Figure 1: Tissue specificity of DPPA5 assay for the detection of semen .......................................................19

Figure 2: Species specificity of DPPA5 Assay for the detection of sperm......................................................20

Figure 3: Sensitivity of the DPPA5 assay for the detection of sperm .............................................................21

Figure 4: Detection of sperm DNA in the presence of DNA from other body fluids ......................................22

Figure 5: Detection of sperm cells in samples of mixed body fluids..............................................................24

Adenosine Deaminase Domain Containing 1 (ADAD1):......................................................................24

Figure 6: Tissue specificity of ADAD1 assay for the detection of sperm .......................................................25

Figure 7: Species specificity of ADAD1 for the detection of sperm................................................................26

Figure 8: Sensitivity of the ADAD1 assay for the detection of sperm cell .....................................................27

Figure 9: Detection of Sperm DNA in the presence of Blood or Saliva DNA ..................................................28

Microseminoprotein-Beta (MSMB).....................................................................................................28

Figure 10: Tissue Specificity of the MSMB assay for the detection of semen ................................................29

Figure 11: Sensitivity of the MSMB assay for the detection of semen...........................................................30

Other gene assays:..............................................................................................................................31

Group I Primers: MSMB-EK2, WFDC, SKP2, UPK3A #1-2 and MMP9 ............................................................31

Group II Primers: UPK3A #3-4, CD52, SPINT2 #1-3.........................................................................................32

Group III Primers: MSMB-EK and MSMB-SC...................................................................................................33

Discussion....................................................................................................................................35

Table 1: Primers and Probes Used in this Study ................................................................................36

Bibliography........................................................................................................................ 42
4

Executive Summary:

Synopsis of the problem and purpose of this research:

When dealing with forensic evidence, time is often of the essence either because a 

suspect has been identified and a court date is eminent or because the perpetrator is not 

known and is roaming free in the population to perhaps strike again (1). Forensic DNA analysis 

has become a victim of its success. Once reserved for only the most violent crimes, genotyping 

has found utility in all types of crimes from property crimes to heinous crimes leading to an 

increasing backlog of evidence (1). A typical piece of biological evidence from a crime scene 

must undergo several types of analyses and procedures prior to the generation of a DNA profile 

that can be used to identify a match, including serological analyses for the identification the 

body fluids, DNA extraction, quantitation, amplification, separation, visualization, interpretation 

and statistical analysis. Initial steps taken to attempt to alleviate this backlog have focused on 

increased personnel and automation in the stages of the analysis from DNA extraction to 

interpretation and statistical analysis. (2). The modifications to this part of the process have 

resulted in eliminating the backlog that existed at the end of the procedure, but have resulted 

in the formation of a new bottleneck. Currently, one of the biggest detractors to the timely 

analysis of DNA based evidence is not the DNA genotyping itself, but the serological 

identification of body fluids that precedes it. (2) 

The purpose of this research was to develop a fully automatable, species specific, 

quantitative method for the identification of body fluids in forensic samples in order to provide 

the forensic community with a method that could help to diminish the bottleneck that has been 

demonstrated at the stage of serological testing.
5

Research design

In order to develop an assay that incorporated all of the characteristics necessary in a 

newly developed procedure, including high sensitivity, high specificity, ease of use and 

relatively low cost; the method of choice was the use of a quantitative methylation specific 

TaqMan® assay. This type of assay utilizes procedures and equipment currently in use in

forensic laboratories across the nation. By taking a portion of a DNA extract, treating it with 

sodium bisulfite to distinguish between methylated and non-methylated cytosine, then using 

DNA primers and labeled DNA probes which preferentially anneal to the treated DNA in a 

polymerase chain reaction, it is possible to quantitatively detect very small quantities of tissue 

specific DNA, thereby identifying tissues which typify blood fluids of interest in a forensic case. 

As the three most commonly identified body fluids are semen, blood and saliva, the 

study was restricted to these body fluids. It is anticipated that once the proof of concept has 

been demonstrated that other body fluids could and should be add to this group of body fluids. 

Additional testing and validation will be required prior to this technique being implemented in 

forensic casework.

Findings and conclusions

Several genes proved to be sufficient for the identification of sperm cells under 

conditions that mimicked conditions that might be seen in forensic casework. DPPA5 and

ADAD1 proved to be as sensitive as the gold standard for the identification of sperm in that 

they were able to detect single sperm cells even in the presence of an overwhelming excess of 

other cell types. This type of assay allows for the quantitation of sperm numbers over at least a 
6

5000 fold range, easily and quickly and in a format which is easily automated, reducing handson analyst time, while maintaining the same high standards for sperm identification. The 

assays for the identification of saliva and blood, proved more problematic in that it was quite 

difficult to find a genes that would allow for specific identification of these body fluids. The 

methylation specific TaqMan® assay proved to be a sensitive assay for the identification sperm 

cells, however identification of blood and saliva were not possible utilizing the primers and 

probes generated in this study. 

Implications for policy and practice

This procedure could be one way in which the backlog of samples in the queue for 

forensic DNA testing is reduced. By providing an automatable method that can identify sperm 

in even very low quantities, this technique could provide a method to reduce the number of 

analyst hours spent on the identification of sperm and allow the analyst to use that time on 

additional tasks that can result in an increase in productivity without an increase in staff or 

costly equipment. 
7

Technical Report:

Goals of the Project:

The purpose of this project was to gather data for the development of a set of genomic

DNA-based Real-Time PCR assays for the identification of forensically relevant biological fluids, 

including blood, semen and saliva from evidentiary samples. By performing serological testing

using a genomic DNA based molecular biological technique as opposed to using traditional 

protein based techniques, it is anticipated that a forensic DNA laboratory could perform a

single preparatory step, DNA extraction, and use this extracted DNA as a substrate for all 

downstream steps in the identification and individualization of the samples. This approach

should allow for (1) identification of body fluids included in the sample, (2) human and/or 

human male quantitation, as well as (3) genotyping from the same extracted DNA. It was the

goal of this project to develop individual assays for the detection of human sperm, blood or

saliva, which could function even in the presence of other cell types from other body fluids.

These assays should match or exceed the sensitivity and specificity of current serological 

procedures commonly used in the forensic community.

The final objective of the proposal was to multiplex the individual methylation

specific quantitative PCR assays developed allowing for the simultaneous detection of the 

presence of blood, sperm and saliva in up to 96 samples at a time, including positive and

negative controls and reagent blanks, utilizing equipment currently in place in forensic 

laboratories in order to dovetail into the current quantitation and genotyping technologies

which could significantly reduce the amount of time and sample necessary for the

identification of body fluids in evidentiary stains.
8

Statement of Problem:

As DNA genotyping has demonstrated its utility, the success of the technique has 

created a burden in many crime laboratories. Once reserved for only the most violent crimes, 

many different types of cases including property crimes have been subjected to DNA

genotyping, resulting in an inability for many crime laboratories to keep up with the 

workload. As the backlog of cases increases, the time from collection of sample and 

submission to the laboratory to production of the final DNA report increases, which may have 

a significant impact on public safety (1). Evidence may sit waiting for analysis allowing 

perpetrators to remain free to commit other, perhaps increasingly violent crimes (3). In most 

laboratories the process of biological evidence analysis involves a workflow that starts with 

visualizing stains followed by serological testing of stains to identify body fluids then DNA 

genotyping analysis for individualization of the sample. To attempt to alleviate the backlog, 

initial efforts have been targeted to automating the process from the point of DNA extraction 

to final analysis (1, 4). These efforts have allowed for a significant decrease in the time it 

takes to perform DNA genotyping on a sample, but has revealed a bottleneck in the process at 

the stage of serological testing. Since most of this process requires hands-on attention of the 

analyst, it can be time- and sample- consuming (2). The most commonly used testing 

practices for blood, semen and saliva are based on identification of proteins, either through 

structure or function. These tests require fairly large amounts of sample, particularly when 

samples must be tested for multiple body fluids (5)
9

Literature Review:

Why perform serology testing?

With the advent of DNA testing procedures that can accurately and efficiently 

determine the genotype of the donor, why even bother with serological testing? Serological 

testing answers questions that genotyping does not. While genotyping allows for the 

identification of WHO had contact, it does not give any information about the type of contact. 

Serological analysis does this. From a criminal justice point of view it can mean the difference 

between the types of charges that are justified. It is the serological results that can corroborate 

a witness statement about the TYPE of interaction; genotyping results can be used to identify 

the parties involved. 

Methods for Body fluid Identification:

The most commonly used methods for the identification of body fluids in crime 

laboratories rely on the identification of proteins that are specifically found in the body fluid in 

question. Since proteins perform most of the critical functions in these body fluids they make 

reasonable targets for identification of these fluids. Common targets are hemoglobin for blood 

(6), alpha amylase for saliva (7), and acid phosphatase (8, 9) or P-30 (prostate specific antigenPSA) for semen (10). Testing for body fluids by detection of these proteins can use a fairly large 

portion of sample in addition to the amount of sample that is necessary for genotyping. Typical 

assays use a sample size 9 mm2to 25mm2(11). In order to test for multiple body fluids, multiple 
10

tests must be performed; thus using additional sample and increasing the time of analysis.

If one recalls that the central dogma of biology describes that genomic DNA is 

transcribed to mRNA, which is then translated to protein (12), it can be easily understood that 

instead of using proteins to identify body fluids it is possible to identify them by looking to 

nucleic acids, both RNA and DNA. By looking at the mRNAs and other small RNAs that are 

unique to cell types it is possible to reduce the amount of analysis time and sample required 

for testing have utilized a shift in approach, by using nucleic acids for testing instead of 

proteins (12). Most of the published methods use either mRNAs or panels of miRNAs in order 

to identify body fluids. (13-19). 

These RNA-based approaches allow for automation of the process, reducing the handson time of the analyst, however the use of RNA as a template requires special handling and 

techniques that may not be easily integrated into the workflow of a typical crime laboratory. 

The mRNA based approaches use panels of genes to infer the origin of the body fluid present. 

Since some of the targets appear in multiple fluids, the identity of a particular body fluid is 

predicted by the presence of groups of mRNAs or miRNAs and performing multivariate 

statistics in order to place the body fluid in a predetermined group.

We chose to develop an assay that that could be simpler to perform from a technical as 

well as a statistical standpoint. By using genomic DNA, which can be more stable than RNA 

under the unfavorable conditions that many forensic samples exist (20), we attempted to use 

signals such as methylation patterns that are used by cells to determine which genes are

transcribed to mRNA and ultimately translated to proteins. Methylation patterns have been 

long recognized as one method used by cells to control gene expression in a tissue-specific or 
11

developmental stage-specific manner (21-24). Recent studies have used methylation specific 

PCR for the identification of forensically relevant body fluids, although these studies did not 

combine this approach with quantitative PCR (5, 25-27). 

Role of Methylation of DNA in Gene Expression:

While methylation of genomic DNA does not alter the sequence of the nucleotides, it 

results in the modification of cytosine residues 5’ to guanosine residues that results in the 

stable alteration of gene expression in many genes (24). Genomic DNA of many vertebrates, 

including humans, have specific regions of highly methylated DNA interspersed with regions of 

non-methylated DNA localized to the 5’ untranslated region of housekeeping genes, 

developmentally- and tissue-specific genes. These unmethylated regions are characterized as 

having a high GC content with clusters of the dinucleotide CpG, and thus have been named CpG 

islands (CGI) (24, 28, 29). 

 Methylation of cytosines in this region can act to silence gene expression, while 

demethylation of 5mC in these regions has been shown to induce expression of previously 

silenced genes (29-31). Methylation acts as an epigenetic switch that can turn off the 

transcription of genes without altering the sequence of the genomic DNA. This can be 

particularly useful for genes that are expressed in a limited number of cell types or in genes that 

are only expressed during different developmental stages of cells. Genes that are under 

methylation control are methylated in non-expressing cells and unmethylated in expressing 

cells.

The production of 5 methyl cytosine (5mC) appears to be mediated by a family of 

enzymes, known as DNA methyltransferases (DNMTs), including DNMT1, DNMT3a, and 
12

DNMT3b in mammals that catalyze the methylation of DNA through an S-adenosyl-methionine 

methyl donor(32). De novo methylation, catalyzed by DNMT3a and DNMT3b, is an important 

feature in the imprinting of methylation pattern during development (33, 34), differentiation 

{Illingworth {Aranyi (22, 23, 29, 35-41). DNMT1 supports the other methyltransferases in the 

maintenance of the methylation patterns once established (32). Production of 5mC has been 

associated with inhibition of DNA transcription by binding of transcription factors, inhibition of 

the formation of active chromatin structures, or by altering the locations of nucleosome 

binding. (21, 42). Although the mechanism for this inhibition is still being elucidated, it is clear 

that the methylation of cytosines in CGI causes a stable inhibition of gene expression through 

the inhibition of transcription. (29, 37)

DNA sequence analysis predicts that the percentage of CpG dinucleotides found in 

the genome is approximately 75% less than would be expected relying on the base composition 

of the genome, except in the CGI, where this motif is enriched. It has been proposed that the 

diminution of the CpG dinucleotides in the genome is due to the ease at which a 5mC is 

converted to thymine by deamination (24). There is a concomitant increase of TpGs and CpAs 

that bolsters 5mC to T conversion supposition.

 The genomic DNA of pluripotent stem cells has been demonstrated to be primarily 

unmethylated, but upon cell differentiation, the overall level of methylation is increased 

through the activity of DNMTs that use CpG pairs as its target (32, 41, 43). Of interest to our 

project, this has been demonstrated in the differentiation of spermogenic germ cells to mature 

spermatozoa (44) and in the differentiation of erythroid progenitor cells to reticulocyte, the 

nucleated immediate precursor to the red blood cell(38, 45). 
13

Genomic DNA may be a more useful molecule to identify a specific body 

fluid. Genomic DNA is found in every nucleated cell and possesses a number of epigenetic 

modifications that allow for tissue specificity, such as DNA methylation, histone modification, 

non-coding RNAs and higher order chromatin structure (34, 43). DNA methylation in particular 

can easily be exploited to link a genomic DNA sequence to a single body fluid type. In animals 

methylcytosine is mainly found in cytosine-guanine (CpG) dinucleotides). About 80% of all 

5’...CpG...3’ dinucleotides in mammalian genomes are found to be methylated, whereas the 

majority of the twenty percent that remain non-methylated are within promoters or in the first 

exons of genes (24). DNA methylation of cytosine residues plays a key role in the regulation of 

gene expression and generally leads to transcriptional silencing in non-expressing cells (23, 34, 

46).

Two different types of methods are currently used to study the degree of methylation in 

DNA sequences: non-bisulfite methods and bisulfite modification methods (47). Non-bisulfite 

methods generally rely on methylation-sensitive restriction endonucleases combined with 

Southern blot or PCR analysis; however, results with this method are limited by the presence of 

corresponding cleavage sites in the gene and area of interest and generally require larger 

sample sizes than are typically used in forensic casework (48). Bisulfite modification methods 

overcome some of the issues associated with non-bisulfite methods. Bisulfite methods are also 

more conducive to forensic applications because they are rapid and require very small amounts 

of DNA sample (30, 49). Bisulfite treatment causes deamination of unmethylated cytosine to 

uracil, while leaving methylated cytosine unchanged. Following treatment, methylation-specific 

(MS)-PCR amplification is performed by engineering primers that anneal to either the 
14

methylated or unmethylated form of the sequence to detect specific sequences and amplifying 

only the template with the appropriate methylation state. Standard PCR does not replicate the 

modifications that are found on DNA, including the methylation of cytosines since the dCTPs 

added to the amplification mixture are not methylated and Taq polymerase will not distinguish 

between the addition of methylated or unmethylated dCTP in the amplified product (50). MSPCR exploits bisulfite-induced changes and utilizes primers designed to a specific methylation 

status and can thus distinguish between expressing and non-expressing cells. Specifically, MSPCR primers are designed to discriminate between methylated and unmethylated alleles 

following bisulfite treatment and to discriminate between DNA modified by bisulfite and that 

which had not been modified (51). By extending this approach to include a dual labeled probe, 

a quantitative TaqMan® assay has be developed to simultaneously detect and quantitate the 

amount of the body fluid present in a sample. Additionally, this method utilizes 

instrumentation and techniques already in use in a forensic DNA lab, providing an excellent 

basis for a new type of serological assay.

Materials and Methods

The method of choice in this study was a methylation-specific TaqMan® assay. This type 

of assay combines the ability to distinguish between methylated and non-methylated cytosines 

due to pretreatment of the DNA samples with sodium bisulfite and the specificity, sensitivity 

and ease of use of a quantitative PCR assay. 

Bioinformatics
15

Genes were chosen for study by one of three methods. Firstly, genes were identified 

through literature searches as being specifically localized to a specific cell type or body fluid. In 

the absence of clear candidates, the TiGER- Tissue-Specific Gene Expression and Regulation 

Database (http://bioinfo.wilmer.jhu.edu/tiger/) was utilized as a tool to identify genes, which 

have been shown by extensive EST data to be expressed in restricted tissues (52). Lastly, the 

reduced representation bisulfite sequencing data from Epigenome Browser at Washington 

University (http://epigenomegateway.wustl.edu/browser/ ) was utilized in conjunction with the 

KEGG pathway feature to compare methylation patterns for genes in the phagocytosis and 

hematopoietic pathways between blood cells and other types of tissues for which this data was 

available (53). Additional literature searches were performed on these genes to obtain 

information about the control of gene regulation. In the absence of any definitive proof of 

methylation control of gene expression, the genomic sequences of these genes were obtained 

and scanned for CpG islands using Methyl Primer Express (Applied Biosystems). If CpG islands 

were identified, primers were designed based on the unmethylated versions of the gene to 

have an annealing temperature of approximately 60C and probes were designed to have an 

annealing temperature of approximately 70C and contain as many CpG sites as possible. This 

was performed either by inspection or with the aid of Meth Primer (54)

(http://www.urogene.org/methprimer/index1.html ). Using the ePCR feature of BiSearch, a 

tool designed to design primers against bisulfite treated genomes, the designed primers and 

probes were amplified in silico to determine the number of PCR products that would be 

expected to be produced in bisulfite treated human and other bisulfite treated genomes, 

including dog, dogfish, chicken, mouse, chimpanzee, rat and yeast. Primer sets that produced 
16

only one PCR product in human and higher primate genomes, but no products in other 

organisms were produced and tested in the laboratory. Primers and probes tested are listed in 

Table 1 at the end of this report. Primers and probes were ordered from IDT DNA Technologies 

(www.idtdna.com ). All Probes were dual labeled with 56FAM and Black Hole Quencher. 

Body Fluid Samples

Blood and saliva were obtained from healthy volunteers under protocols approved by the 

Towson University Institutional Review board. Semen samples were purchased from Lee 

BioSolutions (St Louis, MO). Genomic DNA was extracted by either organic extraction (55) or

using DNA IQ (Promega) following the manufacturers instructions. Genomic DNAs from 

baboon, rhesus monkey, chicken, turkey, pig, cow, salmon, sheep, mouse, rat, cat, dog, mouse, 

rat, ferret, horse, and rabbit were purchased from Zyagen (San Diego, CA). Human DNA was 

quantitated using Quantifiler Human (Life Technologies) following manufacturers instructions 

on the ABI Prism 7000.

Bisulfite treatment of DNA

DNA was bisulfite treated using either the Epitect kit (Qiagen) or the EZ Gold DNA methylation 

kit (Zymo) following manufacturer’s recommended protocols. As quantitation of the low 

quantities (ng range) of treated DNA was not possible following treatment, it was assumed that 

100% yield was obtained following treatment for the purposes of reporting DNA concentrations 

used in the following assays. This probably results in an over reporting of the quantity of the 

DNA, therefore underestimating the sensitivity of the assays.

Quantitative PCR

Quantitative PCR assays were performed using the following basic approach. 100-300nM
17

forward and reverse primers and 100-300nM probe, 0-10 ng bisulfite treated template DNA and 

12.5 L 2x master mix (Fermentas) in a 25ul reaction. All reactions were performed with a 

minimum of 3 replicates. Amplification was performed with an Applied Biosystems ABI Prism 

7000 using the FAM detection filter. Cycling parameters included a 10 minute pretreatment at 

95C followed by 40-50 cycles of 15 second incubation at 95C and 1 minute at and annealing 

temperature of 50-60C. The threshold was set at 0.2 and background determined between 6 

and 15 cycles. Data is reported as the cycle at which the reporter dye crossed the threshold 

(Ct). Each experiment included no template controls. 
18

Results:

A total of 57 sets of primers and probes were generated and screened for this study 

with the goal of developing assays for the detection of sperm, semen, blood and saliva. Many 

of these results were negative and will not be covered in detail. The failed primer sets could be

categorized into two groups: those that did not amplify for any of the body fluids tested, and 

those that amplified for every body fluid tested. This suggests that the methylation status of 

the template sequences tested was similar for all of the body fluids, either fully methylated and 

therefore not amplifiable or unmethylated or having an unmethylated subset of cells and 

therefore amplifiable. However, three of the assays produced interesting results that will be 

discussed in detail in this report. 

Developmental Pluripotency Antigen 5 (DPPA5):

The utility for methylation specific Real time PCR in the detection and identification of

sperm in forensic samples has been demonstrated as a method for identification of sperm 

cells. This approach has led to the development of an assay that rivals the current gold

standard of microscopic examination of evidence in that it has been shown to specifically

detect single sperm cells even in the presence of DNA from other tissues. This assay was

developed using the DPPA5 gene, which has been shown to be methylated in all tissues except

sperm and testes (31). Briefly, DNA is bisulfite treated to convert non-methylated cytosines to

uracils, thereby allowing for the detection of genes that contain no methylated cytosines by 

using primers and probes designed to preferentially amplify non-methylated forms of tissue 

specific genes, i.e. the expressed versions of the genes. The methylation specific quantitative

PCR assay for DPPA5 has been shown to be specific for semen DNA; blood and saliva DNAs 
19

were not detected.

Figure 1: Tissue specificity of DPPA5 assay for the detection of semen

Figure 1: 5 ng of bisulfite treated DNA from semen, blood and saliva were used as a template 

for the Real-Time PCR assay using the DPPA5 primers and probes shown in Table 1. Signal was 

only generated from bisulfite treated seminal DNA; no signal was generated when bisulfite 

treated blood or saliva was used as a template. Signal was also absent in no template control 

and in non-bisulfite treated DNA (data not shown). Data shown is average Ct for triplicate 

assays ± standard deviation and representative of multiple trials.

The species specificity of this assay was determined by performing the assay using 15

different, forensically relevant animals; none of the DNAs were detectable in this assay except 

for the higher primate, Rhesus monkey. All other animals including: Baboon, cow, chicken, 

ferret, rat, mouse, salmon, turkey, pig, cat, dog, horse, rabbit and guinea pig showed no

reactivity in this assay thus demonstrating higher primate specificity for the DPPA5 set of

0

5

10

15

20

25

30

35

40

semen blood saliva

CT

5ng DNA from body fluid
20

primers for the detection of sperm.

Figure 2: Species specificity of DPPA5 Assay for the detection of sperm

Figure 2: Species specificity using 15 forensically relevant non-human species

2 ng of bisulfite treated human semen DNA and 10 ng of bisulfite treated non-human DNAs was 

tested for DPPA5 detection. The human semen signal is indicated. Except for Rhesus monkey 

DNA, all other DNAs are below threshold and therefore not detected.

In order to determine the limit of detection for the DPPA5 assay, varying amounts of 

human semen DNA from 2pg (the DNA contained in a single sperm) to 5ng (the DNA 

contained in 2000 sperm cells) were tested. These quantities were obtained by serial dilution 

of a stock and are presented as a good faith estimate of the DNA quantity tested. The assay 

produced a signal when the equivalent of the DNA from a single sperm cell was used as a 
21

template and produced a linear signal throughout the entire range tested. The sensitivity of 

the assay is unprecedented and matches the sensitivity of microscopic examination of

evidence in that DNA from a single cell is detectable. 

Figure 3: Sensitivity of the DPPA5 assay for the detection of sperm

Figure 3: Sensitivity of DPPA5 detection of bisulfite treated sperm DNA

Serial dilutions of bisulfite treated semen DNA from 2 pg to 5ng of DNA were tested using the 

DPPA5 assay. Data represents average Ct values ± standard deviation of triplicates of a 

representative assay. The signal at this low level of DNA concentration was subject to sampling 

issues and routinely amplified in only one or two of the triplicates and therefore does not 

represent a mean ± standard deviation, only the mean. No signal was obtained with nonbisulfite treated DNA or in the absence of template (not shown). 

It is particularly important in the evaluation of forensic evidence that the assay be 

tested for the detection of sperm DNA in the presence of other body fluids, since mixed 

source body fluids are frequently seen in forensic casework. Mixture studies were performed 

30

32

34

36

38

40

42

44

46

48

0.001 0.01 0.1 1 10 CT

ng semen DNA
22

in which serial dilutions of bisulfite treated sperm DNA (2 pg to 5ng) were mixed with 5ng of

bisulfite treated DNA from either blood or saliva. As little as 2 pg of sperm DNA was detectable

when diluted 1:2500 fold in either blood or saliva DNA with no significant difference in the 

Cycle threshold (Ct) between the three groups. This indicates that the sperm DNA was

detectable without interference from the competing DNAs. In this set of experiments, the

mixture studies have shown that mixtures of previously extracted and bisulfite treated DNAs 

allowed for the detection of sperm DNA at single cell levels even in the overwhelming

presence of other DNAs.

Figure 4: Detection of sperm DNA in the presence of DNA from other body fluids

Figure 5: Mixture Studies: Detection of semen DNA in the presence of other DNA

Serial dilutions of bisulfite treated semen DNA was mixed with 5ng of bisulfite treated DNA 

obtained from either blood or saliva. Each data point represents the average of triplicates 
23

±standard deviation for a representative assay. 

It is important to note that in forensic casework, mixed samples are not combinations

of DNAs, but are mixtures of body fluids. Therefore to test the ability of this assay to detect

sperm in the presence of other body fluids was tested by mixing semen, which had been

diluted 10,000 fold with either blood stains or buccal swabs and then testing for the presence

of sperm, in order to mimic the mixture of body fluids which might be seen in a forensic

sample. This specifically mimics situations in which sperm are found at very low

concentrations in the presence of high concentrations of other fluids. Calculations estimate

that approximately 6 sperm were likely to be present in the portion of the stains use for 

testing. When these diluted semen samples were mixed with full strength concentrations of 

other body fluids, then extracted and bisulfite treated, even these small numbers of sperm

cells were detectable indicating that this assay might be useful in the identification of sperm

in forensic casework samples. 
24

Figure 5: Detection of sperm cells in samples of mixed body fluids

Figure 5: Detection of DPPA5 in casework like samples 

Whole semen was diluted 10,000 fold and 10 μl of the dilution were added to either a dried 

saturated buccal swab or a dried blood saturated filter paper. Approximately 10% of the 

sample was taken for DNA extraction and bisulfite treatment prior to DPPA5 detection. Total 

DNA concentration tested was 5 ng. Data represents the average of triplicates ± standard 

deviation for 4 separate sample sets. 

Adenosine Deaminase Domain Containing 1 (ADAD1):

In order expand the utility of this technique; additional assays for the identification

of sperm were developed and tested. A myriad of genes were evaluated and 8 genes

were found to have CpG islands in which primers and probes could be generated. Of the 8

assays, only one, ADAD1, demonstrated the appropriate specificity for semen, but not

blood or saliva.

0

10

20

30

40

50

60

1 2 3 4

CT

Sample set

Blood

Saliva
25

Figure 6: Tissue specificity of ADAD1 assay for the detection of sperm

Figure 6: The assay demonstrated tissue specificity for semen, as blood and saliva DNA 

were not detected using ADAD1 primers. Data shown is the average of triplicates 

consolidated from 14 different tissue-specificity assays ± standard deviation for a 

representative study.

Once the tissue specificity of the ADAD1 assay had been established, the species 

specificity of this assay was evaluated. 5ng of bisulfite treated human semen DNA was

tested along with 10ng of bisulfite treated DNA from 15 different forensically relevant

species. In this assay the human DNA was the only DNA that reacted.
26

Figure 7: Species specificity of ADAD1 for the detection of sperm

Figure 7: 5ng of human DNA and 10ng of 15 forensically relevant animals were tested in the 

ADAD1 assay. Only the human semen DNA crossed the threshold. The DNA from the non 

human animals was not detected. 

In order to determine the sensitivity of the ADAD1 assay for the detection of semen, 

serial dilutions of bisulfite treated semen from 3pg to 5ng were tested. This assay was capable 

of detecting 3pg of semen DNA, the equivalent of a single sperm cell, as evidenced by the 

reproducible detection of a signal for this dilution, indicating that this assay, like the DPPA5 

assay matches the sensitivity of microscopic visualization of sperm, the current gold standard of 

sperm detection. 
27

Figure 8: Sensitivity of the ADAD1 assay for the detection of sperm cell

Figure 8: A concentration dependent signal is detected down to 3 pg of semen DNA. Data 

shown is the average of quadruplicates ± standard error for a representative study. 

In order to determine the ability of this assay to detect sperm in the presence other 

body fluids, various amounts of bisulfite treated sperm DNA was mixed with 5ng of either 

bisulfite treated DNA from human blood or human saliva and tested in the ADAD1 assay. Even 

in the presence of overwhelming quantities of competing DNA, 8pg of human sperm DNA, the 

equivalent of 2 to 3 sperm cells was detectable. Although this assay was less sensitive than the 

DPPA5 assay, it remains a sensitive assay for the detection of sperm cells. 
28

Figure 9: Detection of Sperm DNA in the presence of Blood or Saliva DNA

Figure 9: 8pg to 5ng of bisulfite treated sperm DNA was mixed with 5 ng of bisulfite treated 

DNA from blood or saliva. Data shown is the average of triplicates ± standard error for a 

representative study.

Microseminoprotein-Beta (MSMB)

As sperm are not always present in all semen samples, for example in semen from

post-vasectomized males, a similar assay was designed for the detection of prostatic cells that 

are also present in semen. We have demonstrated that these cells can be detected in very

low numbers using a methylation specific PCR assay. In experiments similar to those previous

explained, microseminoprotein beta (MSMB) was used as a target for prostate cells. The 

MSMB gene is unmethylated in normal prostate and methylated in prostate cancer.

 MSMB is

expressed only in prostate cells and is therefore a good candidate for this type of assay. The

methylation specific quantitative PCR assay for the detection of MSMB demonstrated semen 

specificity, with no signal generated in when bisulfite-treated blood or saliva DNA was used as
29

a substrate. 

In order to determine if the assay was specific to the unmethylated MSMB gene and 

thus semen, real-time PCR was performed using 5ng of extracted and treated seminal fluid, 

blood and saliva/buccal swabs. For all tests, seminal fluid was amplified with an average Ct 

value of 22. Neither blood nor saliva produced a signal; thus, these fluids were undetected by 

the MSMB RT-PCR assay. When non-treated DNA samples as well as non-template controls 

were tested with the MSMB assay, no signal was detected. Therefore, the MSMB assay is 

specific only to bisulfite-treated seminal fluid DNA. 

Figure 10: Tissue Specificity of the MSMB assay for the detection of semen 

Figure 10: 5 ng of semen, blood and saliva DNA were tested with the MSMB assay for the 

detection of semen. Data shown is the mean +/- standard deviation of triplicate assays. 

In order to determine the sensitivity of this assay, serial dilutions of seminal fluid were 

constructed (dilution concentrations ranged from 5ng to 0.005ng) and amplified in triplicate. 

not detected not detected not detected not detected not detected not detected 

0

5

10

15

20

25

semen blood saliva non-treated

semen

non-treated

blood

non-treated

saliva

no DNA

control

Avg Ct value 

5ng Fluid-Specific DNA 
30

An average Ct value was calculated for each concentration. As expected, the Ct value for each 

consecutive dilution increased with the lowest concentration crossing the threshold well before 

the final amplification cycle (average Ct value is ~34). This concentration is equal to about 1 

cell’s worth of DNA and was consistently detected in repeated trials. Any variation in Ct value 

at this concentration can be accounted for by the fact that one cannot be certain that 1 cell’s 

worth of solely prostatic DNA was amplified. Despite that, this assay appears to be sensitive 

enough to detect the DNA of at least one prostate cell present in seminal fluid.

Figure 11: Sensitivity of the MSMB assay for the detection of semen

Figure 11: 5pg to 5ng of bisulfite treated semen DNA were tested with the MSMB assay for the 

detection of semen. Each data point is the mean +/- standard deviation of the triplicate trials.

When mixture studies were performed however, the detection of semen became

much less sensitive when blood or saliva DNA was introduced. In the presence of other DNAs, 

the sensitivity was lost, at concentrations less than 50 pg of semen DNA, no amplification of 

20

22

24

26

28

30

32

34

36

38

40

0.001 0.01 0.1 1 10 Ct value

ng semen DNA
31

MSMB was detected. This was problematic since it suggests that low concentrations of semen 

when mixed with other body fluids may not be detected in this assay. 

Other gene assays:

We have screened dozens of genes and primers sets for utility in the detection of 

blood and saliva. We have unfortunately been hampered in our progress by a series of failed

experiments. In one subset of these experiments, all of the body fluids amplified. We 

hypothesized that this may be due to populations of hemimethylated DNA in which one 

strand of the DNA contains methylated DNA and the other is unmethylated and therefore a 

potential template for the assay. In order to address these issues that we have seen the 

template DNA was pretreated with DNA methyltransferase I (DNMTI), which fully

methylates hemi- methylated DNA, thus eliminating this as a substrate for the assay. This 

pretreatment has not aided in the differentiation of genomic DNA from different tissues. 

Issues that have been seen in the development of these assays have fallen into three groups,

outlined below.

Group I Primers: MSMB-EK2, WFDC, SKP2, UPK3A #1-2 and MMP9

Primers in Group I produced signals above threshold for blood, semen and saliva. Thus, these 

primers were not selective enough to identify semen. Primer and probe concentrations and 

temperature were adjusted to increase the levels of specificity (data not shown); however, 

significant separation between semen, saliva and blood peaks was not observed. To illustrate, 

smooth amplification curves were observed (~ ct value of 24) for blood, semen and saliva for 
32

UPKA #1 primer set run at 60oC with 300nM primer and probe concentrations; nevertheless, all 

the plots crossed at the Ct value, making it impossible to differentiate the three body fluids 

from one another. Figure 12 is a representation plot of the ct value v. delta Rn for group I 

primers, as mentioned none of the samples crossed threshold.

Figure 12: Representative plot of Group I primers. No tissue specificity is shown. Blood, semen 

and saliva DNA cross the threshold at approximately the same Ct value.

Group II Primers: UPK3A #3-4, CD52, SPINT2 #1-3

Group II primers failed to produce detectable PCR products resulting in none of the samples 

crossing threshold (figure 13). These primers were discontinued for the potential use in 

identifying body fluids following attempts to optimize annealing temperature. 
33

Figure 13: Representative plot of Group II primer illustrating failure to cross threshold

Group III Primers: MSMB-EK and MSMB-SC

Peak separation was observed in Group III primers. Manipulations were made to the 

primer/probe concentrations, temperature, buffer and DNMT treatment). Despite some 

increases in peak separation, complete selectivity for semen was not observed. In particular, 

blood, semen and saliva treated with Dnmt1 for the MSMB-SC primer set resulted in the 

greatest selectivity for semen (ct 22) versus blood and saliva, whose curves appeared jagged 

and trailed just beneath the threshold. Little differentiation between non-DNMT treated saliva 

and semen was observed, Ct 22 and 20 respectively. Figure 14 is a representative plot of the Ct

value v. delta Rn and shows differentiation between semen, saliva and blood peaks. 
34

Figure 14: Representative plot of Group III primers. Notice that semen crosses the threshold, 

however blood and saliva do not.

Group III results were the hardest to interpret because they show clear separation of 

bisulfite treated semen DNA from the others, however when the bisulfite treated DNA from 

body fluids are mixed, there is a significant loss of sensitivity resulting in an assay that is not an 

acceptable method for the detection of semen in cases where the body fluids may be mixed. A 

possible reason for this finding is that once a sample is bisulfite treated the complexity of the 

template is reduced due to the conversion of the four base DNA code to essentially a three 

base code due to the conversion of cytosine to thymine. This might result in the primers 

annealing to multiple places on the genomic DNA, thereby reduning the efficiency of the 

reaction.
35

Discussion

This study has demonstrated a proof of concept for the use of quantitative PCR for the 

detection of sperm cells. Since sperm cells undergo a global demethylation during 

spermatogenesis (56, 57) they are a target-rich source for the development of methylation 

specific quantitative PCR assays that target unmethylated sequences. Unfortunately, the 

identification of unmethylated CpG islands in other tissues and cell types has been more 

problematic. None of the other primer sets and genes that were investigated in this study 

yielded conclusive evidence for the identification of other body fluids. 

Given the number of failed assays, it will be important to develop a more targeted 

approach in order to develop the assay into one that can be utilized in forensic casework.

Currently, a project is being considered in this laboratory to bisulfite treat various body fluids 

in order to obtain whole genome sequencing information to obtain methylation sequence data

for relevant body fluids that can be compared to specifically target sequences that will be

different in different body fluids. Currently available data available compares normal to 

matched tumor sequences and there is little information to be found for bisulfite sequence 

data in normal forensically relevant tissues and fluids. By comparing normal cells from

different body fluids it should be possible to determine areas that are either fully

unmethylated or fully methylated in a single body fluid and target those sequences for 

further study and development of methylation specific quantitative PCR assays. Additionally, 

population studies including bisulfite sequencing of the regions targeted by these assays 

must be obtained in order to perform the developmental validation necessary to implement 

this type of assay in casework.
36

Table 1: Primers and Probes Used in this Study

Body Fluid 

Target Gene Gene Name Primers and Probe

Sperm DPPA5 developmental pluripotency ntigen 5

Forward: 5’- GAAGTGGAAGAGTTGGTAATT-3’

Reverse: 5’-AAAACTCAAAAACAATAAAACCT-3’

Probe: 5’-TTGGATTGTAGTTAGGGTGGTGGG -3’

Sperm ADAD1 adenosine deaminase domain

containing 1 (testis-specific)

Forward: 5’- GTTTTTTTAGAAGGGTAAGGT -3’

Reverse: 5’- TCACTTCAAACCACTCTACACA – 3’

Probe: 5’-TGATGGTTGGTGTTTTTTTTTAGGTGATGTAAGATGTGGA-3’

Sperm ADAM2 disintegrin and metalloproteinase 

domain-containing protein 2

Forward: 5’- TTTTGAGTAGTTGTGATTGTAGGT-3’

Reverse: 5’- AAACACATATTCTTAAATACCACA-3’

Probe: 5’-

AGTAGAGATGGGGTTTTATTGTGTTAGTTAGGATGGTTTTGA-3’

Sperm DDX4 DEAD(Asp-Glu-Ala-Asp) box 

polypeptide 4

Forward: 5’- GAGTAGGAGGAGTTTTGAAGTT-3’

Reverse: 5’-CAAAAAAAATTTATACACAAATAATACTCA-3’

Probe: 5’-AAFTTTTTTTGTTTTGGGGTTTTAGAGTTTTATGGTGTTAA-3’

Sperm GALNTL5

UDP-N-acetyl-alpha-Dgalactosamine:polypeptide Nacetylgalactosaminyltransferase-like 

5

Forward: 5’-TGGGTTAGGATTTGAAAATATT-3’

Reverse: 5’-CATAAACCATCATATCCAATCCA-3’

Probe: 5’-

TTGGGGAATATAGTTTAATTTGTAGTATTATGGTTTGGATTGTTT-3’

Sperm GMCL1L germ cell-less, spermatogenesis 

associated 1 pseudogene 1

Forward: 5’-TTAGAAAAAGGAATTGAAAATAATT-3’

Reverse: 5’-CTAAATTAAAACATAAATTAACATCA-3’

Probe: 5’-TTGGAAATAGTATTTTGAAAATTTTTAGGTTAGTTTTAATTT3’

Sperm KIF2B kinesin family member 2B

Forward: 5’-AGGAGGTGAAAAAATAAAGATGGT-3’

Reverse: 5’-AACATTAAAATTTAATTTATATATCCCA-3’

Probe: 5’-

TTGAGGAGTTTTTTTGGGATTTTGTTGAATATTGAGTTTTGAGAT-3’

Sperm LYZL1 lysozyme-like 1

Forward: 5’-GGATTTGTATGGTATATTATGAGAGT-3’

Reverse: 5’-ATAATCCCATTATCAACTTTCTCA-3’

Probe: 5’-

AGATTAATAGTTTTGTGTGGTGTAGATGTGGAAAGTTGAAGGA-3’
37

Body Fluid 

Target Gene Gene Name Primers and Probe

Sperm MS4A5 membrane-spanning 4-domains, 

subfamily A, member 5

Forward: 5’-AAAATGAAAGTGAAATAGTTAGGT-3’

Reverse: 5’-CCCAACTCACTTCAACTTCCA-3’

Probe: 5’-AGGTTAGGAGTTTGAGATTAGGTTGGTTAATATGGTGAAA-3’

Semen MSMB microseminoprotein, betaForward: 5’-Reverse:

Probe:

Semen MSMB microseminoprotein, betaForward: 5’-ATTTGAATTTTAATAGGTGTTTTGA-3’Reverse: 5’-TACCCAATAATCTAACCAATACAAT-3’

Probe: 5’-TGGAGAGTTTTAGTTATATTTATTGAGTAGGT-3’

Semen MMP9 matrix metallopeptidase 9

Forward: 5’-GGGTTTTTTTTGTATAAGGATGAT-3’

Reverse: 5’-CCAAACTCTACTTCCAAACAAACA-3’

Probe: 5’-AGGGTGAGTTGGGTGTGTTGGTTTGT-3’

Semen CD52 CD52 antigen,

epididymal secretory protein E5

Forward: 5’-GTTTTGTGATTGGGTATGGTGGTTTAT-3’

Reverse: 5’-AATCTCCTAACCTCATAATCCACCCA-3’

Probe: 5’-AGGGTGAGTTGGGTGTGTTGGTTTGT-3’

Semen WFDC2

Forward: 5’-TTAAGGTGGTTGAAATTAGATTTGT-3’

Reverse: 5’-AAAAACAATATCCCAACTATACA-3’

Probe: 5’-AGATAAAGGTGTTGTTGAAATGTAGTTAAGGG-3’

Semen SKP2 S-phase kinase-associated protein 2

Forward: 5’-TGAGTAGTATGTTTGGAGTTGT-3’

Reverse: 5’-ACAACTCATTTACCTATACATAACA-3’

Probe: 5’-TGGGAATTTGGGAGGTGAGTAGTTTTG-3’

Semen UPK3A uroplakin 3A

Forward: 5’-GTTTTTTATTATTTTAGATGGGATT-3’

Reverse: 5’-AATTTTATAAAAAACAAATTTTCTACA-3’

Probe: 5’-AAGGTGTTTGAATTATTTTGAAATTAAATTATTTTTAG-3’

Semen SPINT2 serine peptidase inhibitor, Kunitz 

type, 2

Forward: 5’-TGTAGGTGGTGAGGGTGT-3’

Reverse: 5’-ACACACACAATAAAACACTCA-3’

Probe: 5’-GGTTTGGAAAGGTGATTTTTGGGGG-3’

Semen SPINT2 serine peptidase inhibitor, Kunitz 

type, 2

Forward: 5’-TGTGTTGAGGGGTTTTTTGT-3’

Reverse: 5’-ATAAATACTACATTCTCAATCAACCA-3’

Probe: 5’-GGTGTAGTTGTGTGGGTTGAGGTGG-3’

Semen SPINT2 serine peptidase inhibitor, Kunitz 

type, 2

Forward: 5’-TGTGTGTTGAGAAGGTTGG-3’

Reverse: 5’-ATAAATACTACATTCTCAATCAACCA-3’

Probe: 5’- TGTATTTGATTGTGAGATTTTAATGG-3’
38

Body Fluid 

Target Gene Gene Name Primers and Probe

Semen ACTL7B actin-like 7B

Forward: 5’-AGTTGGTGTGGTTGGTTAGGTT-3’

Reverse: 5’-CATTACTATCCATCTACTCCTACAACAA-3’

Probe: 5’-TGTTTTTGGATATGGGTATTATGTGTGAGATGTT-3’

Blood CR1 complement component (3b/4b) 

receptor 1 (Knops blood group)

Forward: 5’-TTTAGGTGTAGGGGTTTAAGTTGT-3’

Reverse: 5’-AAAACCAAAACTCAATTTCTCAA-3’

Probe: 5’-TGAGTGTAGTGGAAGGTGTAGATGTTGAGTG-3’

Blood CD44 CD44 molecule (Indian blood group)

Forward: 5’-TTGAGGTAGTTTTATTGTTTAGTGG-3’

Reverse: 5’-ACCAAAACTTATCCATAATATCCAAA-3’

Probe: 5’-TGTTTTGTTTTTTGTTGGTTTTTGTTTTGTG-3’

Blood EPOR erythropoietin receptor

Forward: 5’-AGTTTTTTGGAGGTTGTAGTTTTGT-3’

Reverse: 5’-CCAACCTAATATTTAAAATCACATT-3’

Probe: 5’-TGGGGTGTGAATATTTTTTGTGATTA-3’

Blood EPOR erythropoietin receptor

Forward: 5’-GGTTTTTGTTGTTTGAGATATTTATGAT-3’

Reverse: 5’-AAACTAACCTCACCCTCTATACACT-3’

Probe: 5’-TGTTATGAGGTGGATGTTTTGGTTGGTAATGG-3’

Blood MPO myeloperoxidase

Forward: 5’-TGTTGTTTAAGTTAAGTGGTTGT-3’

Reverse: 5’-AAAACACTAACACCAAAAAACTT-3’

Probe: 5’-CATCCAAAACACCTCTCTAAACCCA-3’

Blood MPO myeloperoxidase

Forward: 5’-TGAGGAAGTATTTGTTTATGTATTGT-3’

Reverse: 5’-AATCCTACTTACCTTCCAACACAAC-3’

Probe: 5’-TGTATTGTTAATGTTTTTATTAATGTTTTTTG-3’

Blood MPO myeloperoxidase

Forward: 5’-AATTGATGGAGTAGTATGGTATGT-3’

Reverse: 5’-TACAAACAAAAAATAAACCCACACA-3’

Probe: 5’-TGATATTTGGATGGGTGGTGTGTTTGAG-3’

Blood GP5 glycoprotein V (platelet)

Forward: 5’-GTTATATTTTTGTTGTTGTTTTTGG-3’

Reverse: 5’-TATTTTAATCAATACCCCTTAACACA-3’

Probe: 5’-TGTGTAATAAAATTATGTATTTTTTAGGTGTG

Blood BPGM 2,3-bisphosphoglycerate mutase

Forward: 5’-ATTTTTTGGAAGGAAGTAGGGT-5’

Reverse: 5’-TTTCACCACATTCAAATTTTTCT -3’

Probe: 5’-ATGTTGTTGTATTTAGGGTTTTGGTAGATTTGGT -3’

Blood AZU1 azurocidin 1

Forward: 5’-TTAGGAATTTTGGGGTTAGTATTGT-3’

Reverse: 5’-AATGATTTGATGTTGTTTTAGGTGA-3’

Probe: 5’-TGTTTATGATTTGAGGTGGTGGGAGAGGTA-3’
39

Body Fluid 

Target Gene Gene Name Primers and Probe

Blood AZU1 azurocidin 1

Forward: 5’-TAGTTAGTTTGGTTTGGATGATTTTGT-3’

Reverse: 5’-AACTCTATCCTCCCAATAAAACTACA-3’

Probe: 5’-TGTGAGGGTGGATGGTGTGTGGGATTTAG-3’

Blood AZU1 azurocidin 1

Forward: 5’-AAAAATTAGTTGGGAGTGGTGGTGT-3’

Reverse: 5’-ATTCCTATAATCCCAAACTAATCTCA-3’

Probe: 5’-TGAGGTGGAAGGATGGTTTGAGGTTAGG-3’

Blood AZU1 azurocidin 1

Forward: 5’-TTTTTTGAGATAGAGTTTTGTTTTGTT-3’

Reverse: 5’-AATACAAAATTAACCAAACATAATAACA-3’

Probe: 5’-TGTGATTTTGGTGGTTTATTGTAATTTTTGTT-3’

Blood AZU1 azurocidin 1

Forward: 5’-TTGGTTTTGAATTTTTGATTTTATGATT-3’

Reverse: 5’-CCAACACAAACATAACTCACAACCA-3’

Probe: 5’-TTGTTTGGTTGAGAAATAGTAGTTATTAAAT-3’

Blood PADI4 peptidyl arginine deiminase, type IV

Forward: 5’-AATTTTAGTATTTTGGGAGGTTGAGGTAGGT-3’

Reverse: 5’-TTCTATAACTACATACTACCACACCCA-3’

Probe: 5’-TGAGATTATTTTGGTTAATATGGTGAAATGTT-3’

Blood PADI4 peptidyl arginine deiminase, type IV

Forward: 5’-TTATTTTGGTTAATATGGTGAAATGTT-3’

Reverse: 5’-CAATCTCAATTCACTACAACATCCA-3’

Probe: 5’-TGGGTGTGGTAGTATGTAGTTATAGTTTTA-3’

Blood PADI4 peptidyl arginine deiminase, type IV

Forward: 5’-GTTAGGATGGTTTTGATTTTTGATTTT-3’

Reverse: 5’-ATTCAAAAAAAAACCCAACTAAACACA-3’

Probe: 5’-TGTTTTGGTTTTTTAAAGTGTTGGGATTATA-3’

Blood HBA1 hemoglobin, alpha 1

Forward: 5’-GTGGATGATATGTTTAATGTGTTGTTTGT-3’

Reverse: 5’-CACCCCTCAACCCAAATCAC-3’

Probe: 5’-TGATTTGTATGTGTATAAGTTTTGGGTGGATTTGG-3’

Blood HBA2 hemoglobin, alpha 2

Forward: 5’ATAAGTTTTGGGTGGATTTGGTTAAT-3’

Reverse: 5’-AAACACCATCTCACCCTCAAC-3’

Probe: 5’-TTAAGGTGAGTGGTGGGTTGGGAGTGA-3’

Saliva AQP5 aquaporin 5

Forward: 5’-GGGTGAGGTGGGTTAGGATGTT-3’

Reverse: 5’-TCCATACACAACCTTCCCCTTTTT-3’

Probe: 5’-AAGGAGGAGTTAAAAGTTTGAAGAG-3’

Saliva ZNF480 Zinc finger 480

Forward: 5’-GGATTGTGTGGAGTGAAGGTTAT-3’

Reverse: 5’-CCACCTAACTCTCACAAAAACA-3’

Probe: 5’-

TTGGATTTGAGGGGTTATATAGATTTTGAAATTTTTGTATTGTTT-3’
40

Body Fluid 

Target Gene Gene Name Primers and Probe

Saliva ZNF480 Zinc finger 480

Forward: 5’-TTTTTGTGAGAGTTAGGTGGTT-3’

Reverse: 5’-ATAAACCAAAATCCACCTAACAAA-3’

Probe: 5’-TTTGTTGTGGAGTTTTTTGTTTTAAGTTTTTTAGTGATGTTTA3’

Saliva ZNF480 Zinc finger 480

Forward: 5’-TGTTAGGTGGATTTTGGTTTATGT-3’

Reverse: 5’-AAATAAATCACCTCCCCACACA-3’

Probe:5’TTTTGGAGTATAGTGTTTTAATTTTAATTTAGGAGAAGTTGTGTT3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-GAAGTTATTGGGAGGAGATATTTGA-3’

Reverse: 5’-CACAACAACCTAAACTAAAAACAC-3’

Probe: 5’-AGAGTTGTGTGGGGAAGTTGTGGGATTTTTGG-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-AAGTAGTGTTGGATAGTGATTTTGG-3’

Reverse: 5’-CTCCTCAACCCAAATATAAAAACAA-3’

Probe: 5’-TGTTGGGTATTGATTGGGTTTTGGTATTGGGGAT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-AAGTTTGGTTAGGATGGTATTGAT-3’

Reverse: 5’-ACTATCCCCTAATATCACCCCA-3’

Probe: 5’-TGAGTTTTTTGGTTTGATGGAGAGAAAATTAGGTTTTATTTT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-AAGTTTGGTTAGGATGGTATTGAT-3’

Reverse: 5’-AAAACCACCCCCAATCCCA-3’

Probe: 5’-TGAGTTTTTTGGTTTGATGGAGAGAAAATTAGGTTTTATTTT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TTTGTGAGTGATAATTTTGAAGTAGTT-3’

Reverse: 5’- AATAAACACCAACTATCAACTCTCA-3’

Probe: 5’-TGGTGTAGGTTTTGTTTTGGGTTTTTGTTTTTGTAT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TTAGTGTTTATTTTTTGAGATTGGT-3’

Reverse: 5’-TAACAACATAATCCTCTATCAACCA-3’

Probe: 5’-TTATGTTTGTTTTTGTTTAGTGGGTGTTTGTTGAGGT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TAGGTTTATGGGGGTATTTGT-3’

Reverse: 5’-AAAACCACCCCCAATCCCA-3’

Probe: 5’-TGAGTTTTTTGGTTTGATGGAGAGAAAATTAGGTTTTATTTT-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-AGTTTGAGGTAGAGTTTGGTT-3’

Reverse: 5’-ACTCCAAAATCACTATCCAACA-3’

Probe: 5’-TGTTTTTAGGTTTTTGTTTAGGGTATGGTTTTTTTAGGTT-3
41

Body Fluid 

Target Gene Gene Name Primers and Probe

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-GGAGGGGTTGGTATTTGT-3’

Reverse: 5’-ACTCCAAAATCACTATCCAACA-3’

Probe: 5’-TGTTTTTAGGTTTTTGTTTAGGGTATGGTTTTTTTAGGTT-3

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TTGGTGGTATAGGATATATGAGTT-3’

Reverse: 5’-ACCAAACATCAACCCCCAA-3’

Probe: 5’-TGTTTGGTAGATTTAGTGTTTTTAGTTTAGGTTGTTGTGG-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TGAGGTTTAATAATTTTTTAGAGTTGT-3’

Reverse: 5’-ACCAAACATCAACCCCCAA-3’

Probe: 5’-TGTTTGGTAGATTTAGTGTTTTTAGTTTAGGTTGTTGTGG-3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TGTATATATTTTTTTTAGTTTAGTTATTGT-3’

Reverse: 5’-AAAACTACAATAAACCAAAACAACA-3’

Probe: 5’TGAAGGGAGAATTTTTTTTTATTTATTTTATTGTGGGAGAGATT3’

Saliva COL9A3 collagen, type IX, alpha 3

Forward: 5’-TGATTGTTTTGATGATATTATTTATGGGT-3’

Reverse: 5’- AAAAAAACAACATACCAAAACTCC-3’

Probe: 5’-TGTTGGGGTGGTTTTGGGTTTTTGGGTTT-3’

Skin ELOVL3

elongation of very long chain fatty 

acids (FEN1/Elo2, SUR4/Elo3, 

yeast)-like 3

Forward: 5’-GTAGGTTATAGAGTGTTTAAGTTAGT-3’

Reverse: 5’-CACAACAATAAACACACCCCCTTCCA-3’

Probe: 5’-TGTTGGTTTTTATTGGGGTTGTTTAGTT-3’
42

Bibliography

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