DOI: 10.5061/dryad.15dv41nvd
title: Data from: Mannose-binding lectin gene polymorphisms in the East Siberia and Russian Arctic populations

description: Background: Mannose-binding lectin (MBL) encoded by MBL2 gene is a protein
 with the ability to form carbohydrate complexes with microbial wall
 promoting their subsequent elimination. Genetically determined levels of
 MBL can modify the risk and clinical characteristics of many infectious
 diseases. The frequency of MBL2 genotypes exhibits significant population
 differences. The data on the distribution of MBL2 genotypes among the
 aborigines of the Russian Arctic territories have not yet been published.
 Methods: A total of 880 specimens of dried blood spots of the newborns
 were genotyped. The newborns represented four populations: Nenets,
 Dolgan-Nganasans, Mixed aboriginal population, and Russians (Caucasians,
 Krasnoyarsk). Six polymorphisms of the MBL2 gene were studied: rs11003125,
 rs7096206, rs7095891, rs5030737, rs1800450, and rs1800451. Results: The
 frequency of the combined rare O allele (composed of the coding region
 variants rs5030737, rs1800450, and rs1800451) in the homozygous state was
 significantly higher in Russians: 10% vs 2% in Nenets and 1% in
 Dolgan-Nganosans (p&lt;0.001 for Russians vs other populations). The
 frequency of the high-producing haplotype (HYPA) was 35.4% in the Russian
 newborns, in keeping with European populations (27-33%); 64% for Nenets
 and 56% for Dolgan-Nganasans, similar to the estimates obtained for
 Eskimos and North Amerinds (64-81%). Conclusion: Our study results are in
 line with the hypothesis that human evolution has been moving in the
 direction of accumulation of the genotypes associated with low activity of
 the lectin complement activation pathway because of the prevalence of some
 intracellular infections such as tuberculosis, whereby low MBL activity
 may have a protective effect.
description: A total of 880 specimens of dried blood
 spots for the newborns obtained from the Krasnoyarsk Regional
 Consulting-Diagnostic Centre for Medical Genetics to study the
 prevalence of single nucleotide polymorphisms of <i>MBL2</i>
 gene. The demographic characteristics of the
 studied newborns according to the region of mother’s settlement was the
 same as in our previously published study,[28]. The newborns
 were split into four groups to study ethnic specificity of the
 <i>MBL2</i> polymorphisms: (1) 260 from the Arctic region of
 mother's settlement, from villages with predominantly Nenets
 population (Nenets comprise 85% of the population); (2) 110 from the
 Arctic region of  mother's settlement, from villages with
 predominantly Dolgan-Nganasan population (Dolgan-Nganasans comprise 91% of
 the population); (3) 210 from the Arctic region of mother's
 settlement, from villages with mixed populations with various combination
 of indigenous and alien residents; (4) 300 newborns of European ancestry
 (Russians by self-reports of their mothers) from the city of Krasnoyarsk
 . The study was approved by the Ethical
 Committee of the Scientific Research Institute of Medical Problems of the
 North (# 9 of 8.09.2014). Signed informed consent was obtained
 from parents of all participated children. <b>Blood
 Sample Collection and Genotyping</b> DNA was
 extracted using DIAtomTM DNA Prep kits (“Izogen”, Russia). Genotyping was
 carried out using restriction fragment lengths polymorphism approach
 (RFLP) and real-time polymerase chain reaction. Six polymorphisms of the
 <i>MBL2</i> gene were studied: rs11003125, rs7096206,
 rs7095891, rs5030737, rs1800450 and rs1800451. Genotyping of
 rs1800450 and rs1800451 polymorphisms was performed by RFLP approach. The relevant
 genomic fragment of 349 bp was amplified using the pair of oligonucleotide
 primers: forward 5'-TAGGACAGAGGGCATGCTC-3' and reverse
 5'-CAGGCAGTTTCCTCTGGAAGG-3' (annealing temperature 60˚C).
 Restriction endonucleases <i>AccB</i><i>1
 </i><i>I</i><i> </i>(rs1800450) and
 <i>Mbo II</i> (rs1800451) for hydrolysis of the fragment
 followed by the electrophoresis in agarose gel with ethidium bromide to
 visualise the results. For rs1800450, <i>AccB</i><i>1
 </i><i>I</i> endonuclease produces a single fragment of
 349 bp for the B allele and two fragments of 260 and 89 bp for the A
 allele. For rs1800451, <i>Mbo II</i> endonuclease produces a
 single fragment of 349 bp for the A allele and two fragments of 270 and 79
 bp for the C allele. Four
 polymorphisms rs11003125, rs7096206, rs7095891 and rs5030737 were carried
 out using the real-time polymerase chain reaction approach. The nucleotide
 sequences of allele-specific probes are presented in Table 1.
 <b>Table 1. The nucleotide sequence of allele-specific probes used for genotyping</b> <b>Polymorphism </b> <b>The nucleotide sequence of allele-specific probes</b> <b>Fluorophore – allele</b> <b>rs11003125</b> F – GGGCCAACGTAGTAAGAA R – GGAGTTTGCTTCCCCTTG VIC-C/FAM-G <b>rs7096206</b> F – GCGTTGCTGCTGGAAGAC R – CAATGCACGGTCCCATTTG VIC-G/FAM-C <b>rs7095891</b> F – GGGAAGGTTAATCTCAGTTAA R – CCAGGGATGGGTCATCTATT VIC-A/FAM-G <b>rs5030737</b> F – CTCCAGGCATCAACGGC R – CCAACACGTACCTGGTTC VIC-T/FAM-C   <b>Statistical Analysis</b> Differences in genotypic frequencies between the ethnic groups were assessed using the Pearson’s χ2 test. Haplotypes were assessed and compared between the populations using the <i>haplo.stats</i> package for R. Haplotype score test was applied with 1000 permutations to calculate p-values. Bonferroni correction for multiple testing was duly applied. Statistically significant differences were considered at p&lt;0.05 after correction for multiple testing.
description: Codes for "nationality" column:  
 <b>Nenets
 (</b><b>1</b><b>)</b> 
 <b>Dolgans-Nganasans</b><b> (</b><b>2</b><b>)</b>   <b>Mixed Arctic population (</b><b>3</b><b>)</b> <b>Russians (</b><b>4</b><b>)</b>