bluuebunny/crossref_metadata_2025 huggingface dataset:
Neuronal Activity of Mitral-Tufted Cells in Awake Rats During Passive and Active Odorant Stimulation
Authors: Fuentes Romulo A. , Aguilar Marcelo I. , Aylwin María L. , Maldonado Pedro E.
Published: May 2008

Odorants induce specific modulation of mitral/tufted (MT) cells' firing rate in the mammalian olfactory bulb (OB), inducing temporal patterns of neuronal discharge embedded in an oscillatory local field potential (LFP). While most studies have examined anesthetized animals, little is known about the firing rate and temporal patterns of OB single units and population activity in awake behaving mammals. We examined the firing rate and oscillatory activity of MT cells and LFP signals in behaving rats during two olfactory tasks: passive exposure (PE) and two-alternative (TA) choice discrimination. MT inhibitory responses are predominant in the TA task (76.5%), whereas MT excitatory responses predominate in the PE task (59.2%). Rhythmic discharge in the 12- to 100-Hz range was found in 79.0 and 68.9% of MT cells during PE and TA tasks, respectively. Most odorants presented in PE task increase rhythmic discharges at frequencies >50 Hz, whereas in TA, one of four odorants produced a modest increment <40 Hz. LFP oscillations were clearly modulated by odorants during the TA task, increasing their oscillatory power at frequencies centered at 20 Hz and decreasing power at frequencies >50 Hz. Our results indicate that firing rate responses of MT cells in awake animals are behaviorally modulated with inhibition being a prominent feature of this modulation. The occurrence of oscillatory patterns in single- and multiunitary discharge is also related to stimulation and behavioral context, while the oscillatory patterns of the neuronal population showed a strong dependence on odorant stimulation.
Effect of Intrathecal Administration of Serotoninergic and Noradrenergic Drugs on Postural Performance in Rabbits With Spinal Cord Lesions
Authors: Lyalka V. F. , Musienko P. E. , Orlovsky G. N. , Grillner S. , Deliagina T. G.
Published: May 2008

Our previous studies have shown that extensive spinal lesions at T12 in the rabbit [ventral hemisection (VHS) or 3/4-section that spares one ventral quadrant (VQ)] severely damaged the postural system. When tested on the platform periodically tilted in the frontal plane, VHS and VQ animals typically were not able to perform postural corrective movements by their hindlimbs, although EMG responses (correctly or incorrectly phased) could be observed. We attempted to restore postural control in VHS and VQ rabbits by applying serotoninergic and noradrenergic drugs to the spinal cord below the lesion through the intrathecal cannula. It was found that serotonin and quipazine (5-HT1,2,3 agonist) did not re-establish postural corrective movements. However, when applied during a 10-day period after lesion, these drugs produced a twofold increase of the proportion of correct EMG responses to tilts. It was also found that methoxamine (α1 noradrenergic agonist), as well as the mixture of methoxamine and quipazine, did not re-establish postural corrective movements and did not increase the proportion of correct EMG responses. Serotonin (at later stages) and methoxamine induced periodical bursting in EMGs, suggesting activation of spinal rhythm-generating networks. Appearance of bursting seems to perturb normal operation of postural mechanisms, as suggested by methoxamine-induced abolishment of postural effects of quipazine. When applied in an intact animal, none of the tested drugs affected the value of postural corrections or evoked periodical bursting. We conclude that activation of the serotoninergic system (but not the noradrenergic one) causes selective enhancement of spinal postural reflexes during the earlier postlesion period.
Prenatal Screening and Counseling in Iran and Ethical Dilemmas
Authors: Saniei Mansooreh , Mehr Elnaz Jafari , Shahraz Saeed , Zahedi Ladan Naz , Rad Ala Melati , Sayar Saye , Sherafat Kazemzade Roya , Shekarchi Ahmad , Zali Mohammad Reza
Published: May 2008

Objective: Prenatal screening has become an increasingly common procedure all over the world. It offers couples useful information relating to the health of their fetus, although it faces us with serious ethical dilemmas as well. This study was conducted to find out the attitudes of Iranian scholars towards prenatal screening and counseling with respect to ethical issues. Methods: Two hundred and one physicians, genetic and religious scholars were interviewed with regard to demographics and attitudes towards the ethical dilemmas in prenatal screening and counseling. Interviews were analyzed using the four-principle approach. Results: Findings showed scholars’ attitudes towards: (1) the right of couples to choose prenatal screening, (2) the role of prenatal screening and counseling concerning termination of an affected fetus, (3) screening results and emotional distress in couples, and (4) the impact of prenatal screening and counseling on disability rate. Conclusion: Iranian scholars were willing to consider prenatal screening to help prevent transmission of diseases to the next generation. This goal is attained through the autonomous choice of the couple to participate in prenatal screening and counseling.
The Impact of Genetic Outreach Education and Support to Primary Care on Practitioner’s Confidence and Competence in Dealing with Familial Cancers
Authors: Bethea J. , Qureshi N. , Drury N. , Guilbert P.
Published: May 2008

Aims: To determine the level of competence and confidence in general practice in relation to the management of familial cancers and to determine the impact of providing genetic educational outreach on confidence and competence. Methods: Confidence and competence in dealing with familial cancers was measured using a postal questionnaire sent to all general practitioners and practice nurses in 4 geographical areas in central England. In 2 areas, genetic educational outreach was provided to 10 randomly selected practices and a matched analysis of questionnaire responses before and after intervention was done to determine the impact of the intervention. Results: Respondents were more confident in dealing with patient queries around familial breast cancer risk than those around bowel cancer. This was inconsistent with the ability to correctly assign familial risk, with 48% incorrectly assigning a high-risk categorisation to a low-risk breast cancer scenario. Respondents who had taken part in the intervention reported more confidence in dealing with issues related to the management of patient queries around bowel cancer. Following intervention, participants were more likely to report feeling confident in knowing the relevant family history to collect (72.4% of respondents from participating practices compared to 56.1% from non-participating practices; OR 2.39, p = 0.02, 95% CI 1.14–5.00) and in making a basic assessment of risk (72.4% compared to 38.9%; OR 3.65, p = 0.01, 95% CI 1.38–9.61). Conclusions: Providing genetic educational outreach has a positive impact upon how confident primary care staff feel in dealing with patient queries over familial cancers, particularly in relation to bowel cancer. Further research is needed to explore the impact of providing this service on other relevant outcomes such as appropriateness of referrals to genetic services.
Lessons Learned while Developing a Cancer Family History Campaign in the Columbus, Ohio Metropolitan Area
Authors: Sturm Amy C. , Sweet Kevin , Schwirian Patricia M. , Koenig Clint , Westman Judith , Kelly Kimberly M.
Published: May 2008

This paper discusses the lessons learned by our collaborative, transdisciplinary team while developing a pilot/demonstration educational health campaign geared toward underserved communities in the Columbus, Ohio metropolitan area. The objective of the current study was to determine the feasibility of a campaign to raise awareness of the association between family history and cancer risk and to inform individuals of the availability of Jameslink, an online familial cancer risk assessment tool. The research team included members of The Ohio State University Primary Care Research Institute, which includes a unique combination of expertise in Genetics, Behavioral Science, Social and Health Psychology, Communication, Medicine, and Methodology. The experience of the team in developing university and community partnerships, identifying stakeholders and formulating campaign messages is described. Groups who aided in this process as well as the perspectives they brought to the project are discussed. The lessons learned may be helpful to those developing similar community health projects.
Scintigraphic Imaging of Paediatric Thyroid Dysfunction
Authors: Clerc J. , Monpeyssen H. , Chevalier A. , Amegassi F. , Rodrigue D. , Leger F.A. , Richard B.
Published: May 2008

Imaging of thyroid dysfunction is safe and clinically relevant in children. In congenital hypothyroidism (CH), thyroid imaging permits a precise characterization of the aetiology, which is important for genetic counselling and clinical management. CH may be due to thyroid dysgenesis (ectopia, hypoplasia and athyrosis) or occurs in eutopic glands. In the latter, hypothyroidism may be either transient, especially after iodine overload, or due to permanent autosomal recessive dyshormonogenesis. Thyroid scintigraphy (TS) with either 99mTcO4 or 123I will identify ectopic thyroid tissue, which is the commonest cause of CH. However, recent reports favour the use of 123I, which enhances the accuracy of the aetiological classification. In cases of eutopic thyroid, the measurement of 123I uptake before and after perchlorate administration evaluates the organification process. At all ages, colour Doppler ultrasound scanning (CDU) is helpful in assessing thyroid volume, in identifying nodules and in characterizing tissue vascularization. TS and CDU images of most paediatric thyroid dysfunctions are presented.
Postreceptor Crosstalk on PI3K/Akt between GH and Insulin in Non-Catch-Up Growth Rats Born Small for Gestational Age
Authors: Huang Ting-Ting , Du Minlian , Kuluz John W. , Li Yanhong , Ma Huamei
Published: May 2008

Background/Aims: Children born small for gestational age (SGA) are at increased risk for short stature and type 2 diabetes mellitus as a result of growth hormone (GH) resistance and insulin resistance. The mechanisms of multiple hormone resistance remain unclear. This study was designed to investigate the relationship between GH resistance and insulin resistance in non-catch-up growth (NCU-SGA) rats, and how their signaling pathways are related based on their crosstalk on the insulin receptor substrate-1 phosphatidylinositol 3′-kinase (IRS-1-PI3K) pathway. Methods: NCU-SGA rat model was developed by restricting prenatal food intake in pregnant dams. Activated levels of IRS-1 and Akt in liver protein extracts were compared between NCU-SGA and age- and sex-matched controls born appropriate for gestational age rats at baseline, after insulin stimulation, and after pretreatment with AG490 (GH-JAK2 pathway inhibitor) followed by insulin stimulation. Results: GH secretion was positively related to markedly increased insulin levels in NCU-SGA rats. There was no difference of IRS-1 phosphorylation in response to insulin between two groups, however, insulin-stimulated Akt phosphorylation was attenuated in NCU-SGA rats compared to appropriate for gestational age rats. Pretreatment with AG490 restored the Akt response to insulin demonstrated by significantly increased Akt phosphorylation. Conclusion: GH plays a role in inducing insulin resistance via signaling crosstalk with insulin at the level of PI3K/Akt in NCU-SGA rats.
Graves’ Disease in Brazilian Children and Adults: Lack of Genetic Association with CTLA-4 +49A>G Polymorphism
Authors: Namo Cury Adriano , Longui Carlos Alberto , Kochi Cristiane , Calliari Luiz Eduardo , Scalissi Nilza , Salles João Eduardo , Neves Rocha Mylene , Barbosa de Melo Mônica , Rezende Melo Murilo , Monte Osmar
Published: May 2008

Background/Aim: In several populations, major histocompatibility complex and CTLA-4 (cytotoxic T lymphocyte antigen-4) gene polymorphisms are related to adult subjects with Graves’ disease (GD). Our aim was to study the association of +49A>G polymorphism of the CTLA-4 gene in Brazilian children and adults with GD and its correlation with clinical and laboratory markers of disease severity. Methods: CTLA-4 +49A>G polymorphism was established by polymerase chain reaction-restriction fragment length polymorphism analysis in 44 children and 72 adults with GD and compared to a stringent control group consisting of octogenarians with no history of thyroid disease; free T4 and T3 levels and T3/T4 ratio, antithyroid antibodies, and Graves’ ophthalmopathy were also evaluated according to genotype. Results: No significant difference was found in the frequency of CTLA-4 +49A>G polymorphism among children and adults with GD compared to controls and within groups. There was no significant correlation between the presence of G allele and Graves’ ophthalmopathy, gender, age at diagnosis, and biochemical markers of disease severity. Conclusion: The frequency of CTLA-4 +49A>G polymorphism is not different in children and adults with GD compared to the normal control population and does not seem to contribute independently to the severity of the clinical presentation of GD.
Long-Term Non-Surgical Therapy of Severe Persistent Congenital Hyperinsulinism with Glucagon
Authors: Mohnike K. , Blankenstein O. , Pfuetzner A. , Pötzsch S. , Schober E. , Steiner S. , Hardy O.T. , Grimberg A. , van Waarde W.M.
Published: May 2008

Background: Congenital hyperinsulinism (CHI) is characterized by severe hypoglycemia caused by dysregulated insulin secretion. The long-term outcome is dependent on prevention of hypoglycemic episodes to avoid the high risk of permanent brain damage. Severe cases are usually resistant to diazoxide or nifedipine. In addition, somatostatin analogues are ineffective in a subgroup of patients to achieve stable euglycemia. In these infants the only remaining long-term option has been subtotal pancreatectomy with high risk of diabetes mellitus. Intravenous infusions of glucagon are used as immediate treatment to stabilize euglycemia in affected newborns. The rationale of this treatment comes from the observation of an increased glycogen content of the liver when glycogenolysis is inhibited by insulin. Objective: To review the efficacy and safety of long-term subcutaneous glucagon infusion as a potential therapeutic option for blood glucose stabilization in infants with severe CHI without the need of additional intravenous glucose or immediate surgical intervention. Method: Retrospective review of 9 children with CHI who received continuous subcutaneous infusion of glucagon for weeks or months. Glucagon was added to octreotide to replace octreotide-induced suppression of endogenous glucagon secretion, thereby liberating glucose by stimulation of hepatic glycogenolysis. In 3 cases, a stabilized formulation of glucagon was used to prevent glucagon crystallization that frequently occurs in smaller volumes. Results: Introduction of glucagon allowed the reduction or discontinuation of central glucose infusion in all children studied. In 2 patients, glucagon was introduced due to recurrent hypoglycemia despite subtotal pancreatectomy. Six out of 9 children were discharged home on this treatment, which their parents were able to continue without further symptomatic hypoglycemia, convulsions or unconsciousness. In 3 children, subcutaneous glucagon was continuously administered for 1–4 years leading to stable euglycemia. However, 2 children with diffuse type still required subtotal pancreatectomy. As a possible side effect, 2 children developed erythema necrolyticum, which resolved after discontinuation of the glucagon infusion. This has been described before in glucagonoma. Conclusion: In this retrospective series, combination therapy of low-dose octreotide and subcutaneous glucagon infusion has been effective in preventing hypoglycemic episodes in severe CHI. We propose this may serve as a therapeutic option in place of high rates of glucose infusion through a central venous catheter and as an alternative to subtotal pancreatectomy in diffuse type of CHI.
Potential Benefits of Controlling Coronary Heart Disease Risk Factors in the United Arab Emirates
Authors: Abdulle Abdishakur M. , Nagelkerke Nico J.D. , Abouchacra Samra , Obineche Enyioma N.
Published: May 2008

Background: Cardiovascular risk factors including obesity, diabetes, hypertension, and dyslipidemia, are highly prevalent in the United Arab Emirates. In spite of significant awareness initiatives, little is known about the potential benefits of controlling these risk factors. Aims: To assess the prevalence of preventable risk factors for coronary heart disease (CHD), and the likely benefits of controlling these risk factors. Methods: In a health survey stratified by self-reported hypertension, we enrolled 349 hypertensive and 641 normotensive subjects of diverse ethnicity in Al-Ain city, and measured CHD risk factors. We used the Framingham risk score to estimate the proportion of CHD potentially preventable by controlling hypertension, dyslipidemia, diabetes mellitus (DM), and smoking. Results: Smoking was similar in the two groups (hypertensives 13.2% vs. normotensives 14.2%). The prevalence of diabetes, dyslipidemia [mean (SD) triglycerides, high-density lipoprotein-cholesterol (HDL-C)], overweight/obesity, and thus the 10-year Framingham risk were all significantly (p < 0.001) higher among hypertensive than normotensives. Conclusion: Prevention of type 2 DM, aggressive control of hypertension and dyslipidemia, and smoking cessation could potentially reduce the 10-year incidence of CHD. Barriers include lack of awareness of this problem among the general population and health care providers.
Copy numbers of a clustered long-range repeat determine C-band staining
Authors: Kunze B. , Weichenhan D. , Virks P. , Traut W. , Winking H.
Published: May 2008

A cluster of long-range repeats (LRRs) with a repeat size of roughly 100 kb is part of band D of chromosome 1 of the house mouse, Mus musculus. The cluster is cytogenetically polymorphic: it is either C-band negative or C-band positive. Our results show that the differential staining behavior depends on the LRR copy number and not on differences in DNA composition. There is a threshold between 105 and 175 LRR copies per haploid genome; clusters with lower copy numbers stain C-band negative, whereas those with higher copy numbers are C-band positive. Above this threshold, the size of the C-band is linearly correlated with the LRR copy number. The results imply that sequences capable of forming heterochromatin may be dispersed throughout the genome but are not recognized as such by cytogenetic techniques, unless they reach the threshold amount and concentration.
The human gene encoding the heavy chain of the major histocompatibility complex class I-like Fc receptor (FCGRT) maps to 19q13.3
Authors: Kandil E. , Egashira M. , Miyosi O. , Niikawa N. , Ishibashi T. , Kasahara M.
Published: May 2008

FcRn is an Fc receptor that structurally resembles the major histocompatibility complex class I molecule. In this study, we isolated the human gene encoding the heavy chain of FcRn (FCGRT) and mapped it by fluorescence in situ hybridization to chromosome band 19q13.3. Thus, like its mouse counterpart, the human FCGRT gene is located outside the major histocompatibility complex.
Chromosomal mapping of the genes for the human CDK2/cyclin A-associated proteins p19 (SKP1A and SKP1B) and p45 (SKP2)
Authors: Demetrick D.J. , Zhang H. , Beach D.H.
Published: May 2008

Many gene products associated with the cyclin-dependant kinases (CDKs) have been shown to regulate the active kinase complex during the transition points of the cell cycle. Some of these proteins have been implicated in human neoplasia, acting as either oncoproteins or tumour suppressors. The CDK2/cyclin A kinase complex can complex with several proteins, including p21 and PCNA or p45 p19, and p9. It was previously shown that at least two of these proteins, p19 and p45, are abnormally regulated in transformed cell lines. We describe here the mapping by fluorescence in situ hybridization of the gene for the CDK2/cyclin Aassociated protein p45 (SKP2) to 5p13 and the p19-related genes p19A (SKP1A) and pl9B (SKPIB) to 7q11.2 and 12p12, respectively. All three of these loci are associated with karyotypic alterations, known amplifications, or suspected tumor suppressor genes.
Spatial distribution of sex chromosomes and ribosomal genes: A study on human lymphocytes and testicular cells
Authors: Weipoltshammer K. , Schöfer C. , Almeder M. , Sylvester J. , Wachtler F.
Published: May 2008

The location of the sex chromosomes in relation to the rRNA genes in the nuclei of human lymphocytes and testicular cells was examined. Sex chromosomes were found to be located closer to ribosomal genes than would be expected assuming a random arrangement of these chromosomes with respect to rRNA genes. This proximity could be observed irrespective of the transcriptional activity of ribosomal genes indicating that the chromosomal material and not transcriptional activity is responsible for the intranuclear order of these chromosomes.
The gene encoding protein-tyrosine phosphatase RPTPε (PTPRE) is assigned to human chromosome 10q26
Authors: Melhado I.G. , Anderson L.L. , Duncan A.M.V. , Jirik F.R.
Published: May 2008

Using an ∼1.9-kb cDNA probe, the gene encoding the receptor-like protein-tyrosine phosphatase RPTPΕ (PTPRE) was localized to human chromosome 10q26 by in situ hybridization.
Evolution of the gonosomal heterochromatin of Microtus agrestis: rapid amplification of a large, multimeric, repeat unit containing a 3.0-kb (GATA)11-positive, middle repetitive element
Authors: Kalscheuer V. , Singh A.P. , Nanda I. , Sperling K. , Neitzel H.
Published: May 2008

The sex chromosomes of Microtus agrestis are extremely large due to the accumulation of constitutive heterochromatin. We have cloned and characterized a 2,999-bp (GATA)n-positive sequence, following Haelll digestion, that is confined to the noncentromeric heterochromatin of the X chromosome. The cloned element exhibits an accumulation of certain oligomers, which are scattered throughout its entire length, and several copies of Chi-related sequence motifs, which are thought to be implicated in recombination. The latter might have been responsible for the extensive amplification of homologous genomic elements. The sequence has been amplified to a copy number of 1–2 × 104 within the genome of M. agrestis. In contrast to many satellite DNAs, which are thought to be an inevitable constituent of constitutive heterochromatin, the sequence exhibits a tissue-specific methylation pattern and is organized, not as a simple tandem array, but as a component of an extremely large, multimeric, higher-order repeat unit with a length of over 20 kb. This higher-order repeat accounts for at least 15–30 % of the gonosomal heterochromatin in M. agrestis. Sequences homologous to pMAHAE2 are abundant in the genomes of all Microtus species. The copy number varies from ∼100 per diploid genome in M. arvalis, M. oeconomus, and M. cabrerae to –500 per diploid genome in M. guentheri and up to 1–2 × 104 in M. agrestis. Our molecular data indicate that the sequences of the pMAHAE2 family probably arose during the evolution of the common ancestor of Microtus and have subsequently been amplified extensively in the X chromosomes of M. agrestis in the phylogenetically very short period of less than 1 million years.
A somatic cell hybrid panel for pig regional gene mapping characterized by molecular cytogenetics
Authors: Yerle M. , Echard G. , Robic A. , Mairal A. , Dubut-Fontana C. , Riquet J. , Pinton P. , Milan D. , Lahbib-Mansais Y. , Gellin J.
Published: May 2008

A panel of 27 pig × rodent somatic cell hybrids was produced and characterized cytogenetically. The first step of this study consisted of hybridizing a SINE probe to GTG-banded metaphases of each hybrid clone in order to count and identify the normal pig chromosomes and to detect rearranged ones. The second step consisted of using the DNA of each clone as a probe after pIRS-PCR (porcine interspersed repetitive sequence-polymerase chain reaction) amplification to highly enrich it in pig sequences. These probes, hybridized to normal pig metaphase chromosomes, enabled the identification of the complete porcine complement in the hybrid lines. Whole chromosomes and fragments were characterized quickly and precisely, and results were compared. In addition to this cytogenetic characterization, molecular verification was also carried out by using primers specific to six microsatellites and to one gene previously mapped to pig chromosomes. The results obtained allow us to conclude that we have produced a panel that is informative for all porcine chromosomes. This panel constitutes a highly efficient tool to establish not only assignments of genes and markers but also regional localizations on pig chromosomes.
T-banding pattern of bovine chromosomes and karyotype reconstitution with physically mapped cosmids
Authors: Mezzelani A. , Castiglioni B. , Eggen A. , Ferretti L.
Published: May 2008

Bovine T-banded chromosomes were identified by fluorescence in situ hybridization (FISH) using 27 cosmid probes as chromosome landmarks. Pairwise combinations of probes from chromosomes of markedly different size were co-hybridized to metaphase spreads of T-banded chromosomes. This confirmed the association of banding patterns to individual chromosomes. The T-banding pattern appears to be related to R-bands: 80% of T-bands were in corresponding position to R-bands, but not always conserved in size. Band assignments placed 20 probes on similar bands in both patterns. The identification of T-banded chromosomes represents a first step toward the construction of a compositional map of the bovine genome and an additional tool for its study on a comparative basis.
Ordering of 66 STSs along the entire short arm of human chromosome 17 and chromosome assignment of a transcribed sequence (FMR1L2) homologous to FMR1
Authors: Wilgenbus K.K. , Coy J.F. , Mincheva A. , Nicolai H. , Solomon E. , Lichter P. , Poustka A.
Published: May 2008

Sixty-four PCR-markers previously assigned to the short arm of chromosome 17 and two newly established STSs were localized on a hybrid cell-YAC clone panel. The 66 STSs fell into 23 unique retention patterns, providing a map covering the entire short arm of human chromosome 17 with an average resolution of approximately 1.2 Mb. The combination of radiation-reduced hybrids, somatic cell hybrids and selected YAC clones enabled the precise localization of breakpoints in two cell hybrids. Since polymoφhic STSs from the CEPH as well as the UTAH genetic map were used in this study, a physical link has been generated between these two high resolution genetic maps. FMR1L2, a second FMR1 autosomal homologue has been identified and assigned to a genomic interval between D17S796 and D17S799.
Sex-linkage of glucosephosphate isomerase-B and mapping of the sex-determining gene in channel catfish
Authors: Liu Q. , Goudie C.A. , Simco B.A. , Davis K.B.
Published: May 2008

Sex-linkage of glucosephosphate isomerase-B (GPI-B) was observed in five experimental matings between heterozygous male and homozygous female channel catfish (Ictalurus punctatus). Offspring phenotypes for GPI-B were 40.8% heterozygous male and 43.0% homozygous female, while recombinant offspring were 7.4% homozygous male and 8.8% heterozygous female. Thus, GPI-B and the sex-determining gene (SDG) were linked and had a recombination rate of 16.2%. This linkage was designated I. punctatus linkage group XXIX. The gene-centromere distance (1.66 cM) of SDG, estimated in six gynogenetic families derived from XY females, indicated that SDG resides very close to the centromere. Based on estimates of these genetic distances, a chromosomal order of GPI-B-centromere-SDG was proposed. Additionally, joint segregation of GPI-A and SDG in two experimental matings indicated no genetic linkage between GPI-A and sex. These genetic relationships were compared to those reported in other teleost taxa with regard to evolutionary conservation of ancestral gene arrangements.
Genetic mapping of the mouse stromal cell-derived factor gene (Sdf1) to mouse and rat chromosomes
Authors: Nomura M. , Matsuda Y. , Itoh H. , Hori T. , Suzuki G.
Published: May 2008

Stromal cell-derived factor 1 (SDFl) is a new member of the Cys-X-Cys chemokine family. The chromosomal location of Sdf1, the gene coding mouse SDF1, was determined by fluorescence in situ hybridization (FISH) and molecular linkage analysis. The mouse Sdf1 gene was localized to the R-band-positive Fl band of chromosome 6 by direct R-band-ing FISH. Interspecific backcross analysis identified the mouse Sdf1 gene locus at 0.8 cM terminal to D6Nit55 and 3.0 cM proximal to D6Mit12. With in situ hybridization using a mouse cDNA clone as a probe, the rat Sdf1 gene was localized to the R-band-positive band 4q42.1, where conserved linkage homology to mouse chromosome 6 has been identified. Although other Cys-X-Cys chemokine genes have been mapped on human chromosome 4, the chromosomal segment where the mouse and rat Sdf1l gene reside have no conserved linkage homology to human chromosome 4. This result suggests that SDF1 is a new chemokine class.
Genetic linkage mapping of the human steroid 5α-reductase type 2 gene (SRD5A2) close to D2S352 on chromosome region 2p23→p22
Authors: Morissette J. , Durocher F. , Leblanc J.-F. , Normand T. , Labrie F. , Simard J.
Published: May 2008

Two steroid 5α-reductase isoenzymes catalyze the conversion of testosterone into dihydrotestosterone, the more bioactive androgen, which is essential for male phenotypic sexual differentiation and for androgen-mediated growth of such tissues and organs as the prostate. Inherited mutations in SRD5A2 cause male pseudohermaphroditism. The SRD5A1 and SRD5A2 genes encoding the steroid 5α-reductase type 1 and type 2 isoenzymes have been previously assigned by in situ hybridization to 5p15 and 2p23, respectively. To map the SRD5A2 gene by linkage analysis, a novel RsaI RFLP detected in exon I and a TA repeat polymorphism found in exon V were genotyped in eight CEPH reference families. A two-point linkage analysis was performed between these polymorphisms and the chromosome 2 microsatellite markers of Généthon and NIH/CEPH. The closest linkage was observed with D2S352 (Zmax = 24.06; Θmax = 0.001) in the region 2p23→p22. To further define the localization of SRD5A2, a framework map, including nine Généthon markers flanking the polymorphic SRD5A2 locus, was built by multipoint linkage analysis. This led to a high-resolution genetic map of the region flanking the polymorphic SRD5A2 gene, including the nine Généthon markers and three NIH/CEPH markers, yielded the following order: tel-D2S48-D2S149-D2S320-D2S171-D2S165-[D2S352/SRD5A2]-D2S367-[D2S19/D2S177]-[D2S391/ CALM]-D2S378-cen.
Coding sequence and chromosome mapping of the human gene (CDC46) for replication protein hCdc46/Mcm5
Authors: Paul R. , Hu B. , Musahl C. , Hameister H. , Knippers R.
Published: May 2008

We have isolated the complete cDNA sequence encoding the human homolog of the yeast replication protein Cdc46/Mcm5. The cDNA was used as a probe for chromosomal fluorescence in situ hybridization (FISH), which localized the human Cdc46 gene (CDC46) to chromosome region 22q13.1→q13.2. This is the fourth human Mem gene whose chromosome region has been determined, and it is now apparent that human Mem genes are widely distributed in the genome. As deduced from the cDNA sequence, human protein hCdc46 is composed of 734 amino acids and contains a central region that is almost 80% identical with the yeast protein. Immunoprecipitation experiments with hCdc46-specific antibodies confirm that essentially all nuclear hCdc46 proteins form a stable dimeric complex with protein P1 Mcm3.
Analysis of CA repeat polymorphisms places three human gene loci on the 8p linkage map
Authors: Bruskiewich R. , Everson T. , Ma L. , Chan L. , Schertzer M. , Giacobino J.-P. , Muzzin P. , Wood S.
Published: May 2008

The gene loci for luteinizing hormone-releasing hormone (LHRH), the beta-3 adrenergic receptor (ADRB3), and heregulin (HGL) have been assigned to the short arm of human chromosome 8, but the positions of these loci on the human genetic linkage map have not been previously reported. We have isolated simple tandem repeat polymorphisms (STRPs) for these loci. These STRPs enabled us to determine the genetic map locations for these genes.
Identification and mapping of type 1 neurofibromatosis (NF1) homologous loci
Authors: Cummings L.M. , Trent J.M. , Marchuk D.A.
Published: May 2008

During the establishment of a YAC contig for the type 1 neurofibromatosis (NF1) region on human chromosome 17q11.2, several YAC clones were isolated which originated from a different chromosome but which retained strong homology to NFl coding regions (Marchuk et al., 1992). Fluorescence in situ hybridization (FISH) using these clones has identified NFl-homologous loci on several human chromosomes, including 2, 14, 15, 21, and 22. PCR amplification using primers originally designed to amplify NF1 exons has confirmed these chromosome localizations and, in addition, has revealed NF1-homologous sequences on chromosomes 12 and 20. Sequence analysis of the amplified products has demonstrated that most of these loci have >90% identity with NFl sequences; most of these loci represent nonprocessed pseudogenes; and for the chromosome 12 locus, the two described regions of homology with NF1 have open reading frames. Finally, we have identified two novel α-satellite DNA repeat units in proximity to NF1-homologous sequences on chromosome 14. Their association suggests a mechanism for dispersion of the NF1-homologous loci based on α-satellite-mediated exchange between nonhomologous chromosomes.
Point mutation analysis of archived cytogenetic slide DNA
Authors: Sago H. , Goldberg J.D. , Lebo R.V.
Published: May 2008

Archived Giemsa-stained cytogenetic slide repositories represent valuable DNA resources for medical, scientific, and forensic studies. Sequencing readily identified a Charcot-Marie-Tooth disease point mutation in a 209-bp PCR amplified product. With optimal PCR primers and amplification conditions, our protocol quickly and reliably isolated sufficient DNA for at least 12 independent PCR amplification reactions for forensic and medical applications from single slides up to 5 years old.
Localization of the human IL-2-inducible T-cell kinase gene (ITK) to chromosome band 5q34 and the mouse gene (Itk) to chromosome 15 by fluorescence in situ hybridization
Authors: Tate G. , Okuyama M. , Okamoto M. , Futaki G. , Kimura S. , Endo Y. , Mitsuya T. , Katagiri M.
Published: May 2008

ITK, predominantly expressed on T cells and myeloid cells, is a member of the Tec nonreceptor tyrosine kinase family. Both human ITK and mouse Itk genomic clones were isolated to assign the chromosome location. The human ITK gene was mapped to chromosome band 5q34 and the mouse gene to chromosome 15 by fluorescence in situ hybridization.
Analysis of radiation-induced micronuclei in two-cell human-hamster embryos using telomeric and centromeric FISH probes
Authors: Tusell L. , Alvarez R. , Genescà A. , Caballín M.R. , Miró R. , Egozcue J.
Published: May 2008

Simultaneous, fluorescent in situ hybridization using a centromeric human alpha satellite DNA probe and a telomeric DNA probe was used to analyze the chromosome content of micronuclei induced in two-cell human-hamster embryos by in vitro Γ-ray irradiation of human spermatozoa. In unirradiated samples, about 26 % of micronuclei were centromere positive, indicating that both structural chromosome aberrations and numerical changes are involved in the spontaneous production of micronuclei. After exposure of spermatozoa to radiation, a significant increase in the number of micro-nuclei was found. About 77% of induced micronuclei contained only telomeric signals suggesting that they originated from acentric fragments. However, both centromere-positive and centromere-negative micronuclei increased with radiation dose. These results are consistent with the well known clastogenic effect of ionizing radiation and with its weak an eugenic effect.
Chromosomal assignment of the Bcl2-related genes, Bcl2l and Bax, in the mouse and rat
Authors: Matsuda Y. , Kusano H. , Tsujimoto Y.
Published: May 2008

The Bcl2-related genes, Bax and Bcl2l (formerly called Bclx), are involved in the regulation of apoptotic cell death, and the chromosome location of these two genes was determined in the mouse and rat by fluorescence in situ hybridization. Bcl2l was localized to mouse chromosome 2H1 and rat chromosome 3q41.2, and BΑx was localized to mouse chromosome 7B5 and rat chromosome 1q31.2. Both genes mapped in a region of conserved linkage homology between the two species. Molecular linkage analysis using interspecific backcross mice revealed the murine Bcl21 locus at 0.7 cM terminal to D2MU22, and the murine BΑx locus at 0.8 cM terminal to D7Nds5.
Gene localization and syntenic mapping by FISH in the dog
Authors: Dutra A.S. , Mignot E. , Puck J.M.
Published: May 2008

To begin development of a canine gene map and to define syntenic regions between the canine and human genomes, the technique of fluorescence in situ hybridization (FISH) was adapted to localize specific DNA sequences in canine metaphases. Genomic clones of canine origin as well as human yeast artificial chromosome clones were used to map canine loci. The immunoglobulin heavy-chain region was localized to canine chromosome 4qtel; the canine major histocompatibility locus, DLA, was found to be on chromosome 12qtel. Of particular interest, the canine X chromosome, which morphologically is highly similar to the human X, also showed syntenic localization of the clotting factor VIII (F8C) and factor IX (F9) genes to Xq28 and Xq26.3→q27.1, respectively.
Molecular cloning of a human cDNA encoding putative cysteine protease (PRSC1) and its chromosome assignment to 14q32.1
Authors: Tanaka T. , Inazawa J. , Nakamura Y.
Published: May 2008

We have isolated a novel human cDNA encoding a protein of 433 amino acids which shows 40% sequence identity to a hemoglobinase of SchÍstosoma japonicum, one of the cysteine proteases in the pathway by which trematodes degrade host-cell globin. It also has 36 % identity to a cysteine protease of the soybean Glycine max that processes proproteins of various vacuolar proteins into mature form after translation. Con sidering the sequence similarities among these proteins in such widely divergent species, the human cDNA reported here appears to represent one of a group of genes that have been well conserved during evolution. Northern-blot analysis revealed the strongest expression of this gene in kidney, among the human tissues examined. By fluorescence in situ hybridization, we determined its chromosome location at 14q32.1.
Isolation and mapping of the human glycoprotein M6 gene (GPM6A) to 4q33→q34
Authors: Shimizu F. , Watanabe T.K. , Fujiwara T. , Takahashi E. , Nakamura Y. , Maekawa H.
Published: May 2008

We have isolated a human cDNA that is highly homologous to the murine gene (Gpm6) encoding a membrane glycoprotein, M6. The human gene (GPM6A) contains an open reading frame of 834 nucleotides encoding a peptide of 278 amino acids. Northern-blot analysis revealed specific expression in human brain. We assigned the GPM6A locus to chromosome bands 4q33→q34 by radiation hybrid mapping.
Molecular cloning of UBE2G, encoding a human skeletal muscle-specific ubiquitin-conjugating enzyme homologous to UBC7 of C. elegans
Authors: Watanabe T.K. , Kawai A. , Fujiwara T. , Maekawa H. , Hirai Y. , Nakamura Y. , Takahashi E.
Published: May 2008

From a human fetal-brain cDNA library we isolated a novel ubiquitin-conjugating enzyme. The cDNA, designated UBE2G, contained an open reading frame of 510 nucleo-tides encoding 170 amino acids. The predicted peptide product showed 74% identity at the amino acid level with UBC7 of C. elegΑns, a high degree of homology with UBC7s of other species, and significant homologies with other subgroups of UBCs. Northern-blot analysis revealed strong expression of 4.4-kb, 2.4-kb, and 1.6-kb transcripts in skeletal muscle. Weak expression was observed in 15 other tissues examined. Radiation-hybrid mapping localized this cDNA to chromosome band lq42.
Isolation, characterization and chromosomal assignment of the human WNT7A gene
Authors: Ikegawa S. , Kumano Y. , Okui K. , Fujiwara T. , Takahashi E. , Nakamura Y.
Published: May 2008

The Wnt genes compose a large gene family encoding a group of secreted signaling molecules that have been implicated in oncogenesis and a number of developmental processes. We have isolated a full-length human cDNA clone that we consider to be a novel member of the Wnt gene family. The gene (WNT7A) encodes a deduced 349-amino-acid peptide with 98% identity in amino acid sequence to murine Wnt7a. Expression of this gene is restricted to certain tissues: placenta, kidney, testis, uterus, fetal lung, and fetal and adult brain. Furthermore, we have isolated a genomic clone of WNT7A and mapped it to chromosome 3p25 by fluorescent in situ hybridization.
FISH mapping of centromere protein C (CENPC) on human chromosome 4q13→q21
Authors: Xie Y. , Heng H.H.Q.
Published: May 2008

Centromere protein C (CENP-C), a human centromere autoantigen, is a component of the inner kinetochore plate. CENP-C is required for maintaining proper kinetochore size and a timely transition to anaphase. In this study using fluorescence in situ hybridization to metaphase chromosomes, the human CENP-C gene (CENPC) was mapped on chromosome 4, region q13→q21.
An analysis of human sperm chromosome aneuploidy
Authors: Templado C. , Márquez C. , Munné S. , Colls P. , Martorell M.R. , Cieply K. , Benet J. , Van Kirk V. , Navarro J. , Estop A.M.
Published: May 2008

A sperm chromosome analysis of 24 men with normal or balanced karyotypes was carried out to study the frequency of sperm chromosome aneuploidy. A total of 3,446 human sperm complements (36–315 per donor) was analyzed after in vitro penetration of hamster eggs. Two sets of donors were studied at two different centers in the United States (center 1) and Spain (center 2). The frequencies of hyperhaploidy and hypohaploidy in control donors were similar between center 1 (1.9% vs. 7.7%) and center 2 (1.8% vs. 10.3%). In carrier donors there were no significant differences between the two centers in the frequency of hyperhaploidy (0.8 % vs. 1.9 %), but that of hypohaploidy was significantly higher in center 2 (11.0%) than in center 1 (4.6%). A significant excess of hypohaploid complements, as compared to hyperhaploid complements, was found in both centers in both control and carrier donors. The sex ratio was similar in both centers and did not differ significantly from a 1:1 sex ratio. The larger chromosomes in the complement (1, 2, 3, 4, 5, 7, and 10) presented a significantly lower frequency of hypohaploidy, while some of the smaller chromosomes (13, 19, and 21) showed a higher frequency of hypohaploidy than expected. Chromosome 21 and the sex chromosomes showed an increase in the percentage of hyperhaploidy, as compared to other chromosomes, that was close to statistical significance (P = 0.08). Our results reflect a preferential loss of small chromosomes during slide preparation and suggest that chromosome 21 and the sex chromosomes could be more frequently involved in aneuploidy.
Localization of the gene for the human MIG cytokine on chromosome 4q21 adjacent to INP10 reveals a chemokine “mini-cluster”
Authors: Lee H.-H , Farber J.M.
Published: May 2008

MIG is a gamma interferon-inducible T cell chemoattractant that is a member of the chemokine family of cytokines. P1 clones containing the MIG gene were found also to contain the gene of a related chemokine, INP10. We localized MIG and INP10 to 4q21 by FISH, demonstrated by pulsed field gel electrophoresis that MIG and INP10 are distant from the tight cluster of other CXC chemokine genes at 4q12→q13, and determined that MIG and INP10 are oriented head to tail with their start codons separated by less than 16 kb.
Isolation and mapping of RAB2L, a human cDNA that encodes a protein homologous to RalGDS
Authors: Isomura M. , Okui K. , Fujiwara T. , Shin S. , Nakamura Y.
Published: May 2008

We have isolated a novel human cDNA, designated RAB2L, that encodes a protein homologous to Ral guanine nucleotide dissociation stimulator (RalGDS). The predicted sequence of 122 amino acids revealed 39.5% identity with the C-terminal region of human RalGDS. As the C-terminal region of RalGDS is considered to interact with RAS, the product of this novel gene may also play some role in the ras-mediated signal transduction pathway. Northern analysis revealed that the gene RAB2L is expressed in all human tissues examined. We assigned this gene locus to chromosome band 6p21.3 by fluorescence in situ hybridization.
Generation and mapping of human chromosome 2 microdissection clone-derived STSs
Authors: Gingrich J.C. , Garnes J.A. , Lee D.A. , Boehrer D.M.
Published: May 2008

Twenty-nine new sequence-tagged sites (STSs) were derived from DNA sequences of clones from two human chromosome 2 microdissection libraries. The specificity of the STSs for human chromosome 2 was first demonstrated by PCR amplification of DNA from genomic human and hamster cells and a human chromosome 2-containing human × hamster hybrid cell line. The STSs were then mapped to chromosome 2 by two different approaches. In the first attempt, 12 of the STSs were shown to PCR amplify YAC clones associated with genetic markers on the chromosome. In the second approach, 27 of the STSs were localized to chromosome bands by FISH using cosmid or PAC clones encoding the STSs. The specific STSs mapped to chromosome 2 by these two approaches tie together the genetic and cytogenetic maps of the chromosome at the two termini. The distribution of these STSs further defines the region of the chromosome present in the two microdissection libraries.
Mapping of the genetically independent chicken major histocompatibility complexes B@ and RFP-Y@ to the same microchromosome by two-color fluorescent in situ hybridization
Authors: Fillon V. , Zoorob R. , Yerle M. , Auffray C. , Vignal A.
Published: May 2008

The chicken MHC is organized in two genetically independent gene complexes B@and RFP-Y®. Previous studies have shown the localization of the B@complex on a small microchromosome. By using two-color fluorescent in situ hybridization, we demonstrate the localization of the RFP-Y@ complex to the same chromosome. A recombination hot spot between the two loci might account for their independent segregation.
A finding of the XX/XY1Y2 sex-chromosome system in Taterillus arenarius(Gerbillinae, Rodentia) and its phylogenetic implications
Authors: Volobouev V. , Granjon L.
Published: May 2008

A chromosome banding study (R- and C-bands) of a male Taterillus arenarius (Rodentia, Gerbillinae) specimen from Mauritania revealed the presence of an XX/XY1 Y2 sex-chromosome system in the karyotype, as found previously in three other congeneric species. This finding allowed us to resolve the phylogenetic affinities of this species within the genus and to propose an evolutionary scenario leading to the formation of the species with an XX/XY1 Y2 sex-chromosome system. A review of chromosome data in Taterillus suggests that there may be more species in the genus than hitherto recognized.