中国朝鲜族H19基因上游差异甲基化区SNP分布

目的调查中国朝鲜族群体中H19基因上游差异甲基化区(differentially methylated region,DMR)SNP及单倍型分布,为法医学应用及群体遗传学研究提供基础数据。方法收集中国朝鲜族101份无关个体血样和14份来自5个亲缘关系已知的两代家系血样,用PCR-循环测序、McrBC消化DNA后PCR方法检测H19基因上游DMR的SNP,并用亲源印记等位基因(parentally imprinted allele,PIA)分型法进行单倍型检测,再计算相关遗传学参数。结果在H19基因上游DMR 1174bp的目的基因扩增产物中,共检出13个SNP(rs10840167、rs2525883、rs12417375、rs4930101、rs2525882、rs2735970、rs2735971、rs11042170、rs2735972、rs10732516、rs2071094、rs2107425、rs4930098)和5种单倍型,有9个SNP属于高鉴别能力的遗传标记,其单倍型具有较高的个人识别率,单倍型平均基因多样性(GD)为0.714。应用McrBC酶消化基因组DNA的PIA分型法确定了家系子代样本的母源单倍型。结论 H19基因上游DMR在中国朝鲜族群体中具有很高的遗传多态性,母源单倍型的确定进一步提高了印记基因的法医学鉴定效能。

SNP in Differentially Methylated Region Upstream of H19 Gene in Chinese Kore-an Nationality

Objective To investigate SNP and distribution of haplotypes in differentially m ethylated region （DMR） upstream of H19 gene in Chinese Korean nationality in order to provide basic data for forensic application and population genetics research. Methods One hundred and one blood sam ples from unrelat-ed Chinese Korean individuals and 14 blood sam ples from 5 Chinese Korean intergenerational fam ilies which known genetic relationship were collected. The SNP in DMRupstream of H19 gene were investi-gated by PCR-cycle sequencing and McrB Cdigestion followed by PCR . The haplotypes detected by parentally im printed allele （PIA） m ethod and relevant genetic param eters were calculated. Results Thirteen SNPs （rs10840167, rs2525883, rs12417375, rs4930101, rs2525882, rs2735970, rs2735971, rs11042170, rs2735972, rs10732516, rs2071094, rs2107425, and rs4930098） and five haplotypes were detected in 1 174 bp target product in DMRupstream of H19 gene, with 9 SNPs having high discrim ination power as good genetic markers. The average gene diversity （GD） of haplotypes was 0.714. The maternal haplotype was confirm ed correctly by PIAm ethod from McrB C-digested products of genom ic DNA. Conclusion High polym orphism sexist in DMRupstream of H19 gene in Chinese Korean nationality. And determ ination of the maternal haplotype could furtherm ore enhance the forensic identification efficiency of im printed gene.