深圳地区汉族无偿献血人群Kidd血型系统基因多态性的分子遗传学研究

Molecular genetic study on gene polymorphism of Kidd blood group system of voluntary blood donors in Shenzhen Han population

目的 探讨深圳地区汉族无偿献血人群Kidd血型系统基因多态性的分子遗传学背景.方法 采用简单随机抽样法选择2015年1月至2015年12月于深圳市血液中心无偿献血的74例汉族献血者为研究对象.采用红细胞尿素溶血试验及常规血清学方法鉴定献血者的Kidd血型表型.采用PCR扩增JK基因第4～11外显子及部分内含子片段,并且采用直接测序法对PCR扩增产物进行序列分析.结果 ①74例献血者的Kidd血型表型分别为Jk(a+b+)37例,Jk(a+b-)16例,Jk(a-b+)21例,未筛查出稀有Kidd血型表型Jk(a-b-).②74例献血者的DNA样本均成功扩增JK基因第4～5外显子、第6外显子、第7外显子、第8～9外显子、第10外显子、第11外显子区域.③DNA序列分析结果显示,37例Jk(a+b+)表型献血者DNA样本中,JK基因存在第9外显子c.838G＞A和第7内含子c.664-68C＞T杂合突变.21例Jk(a-b+)表型献血者DNA样本中,JK基因为c.838AA和c.664-68CC纯合型,而16例Jk(a+b-)表型献血者DNA样本中,JK基因为c.838GG和c.664-68TT纯合型.74例献血者DNA样本中,JK基因均为第8内含子c.811+84TT纯合型.结论 深圳地区汉族献血人群Kidd血型系统中,除存在JK基因第9外显子c.838G＞A(p.Asp280Asn)突变以外,还存在第7内含子c.664-68C＞T碱基置换,该突变可能与JKa/JKb基因多态性相关.并且JK基因第8内含子均为c.811+84TT纯合型,其在中国人群中属于常见的基因型.

Objective To explore the molecular genetic background of the Kidd blood group gene polymorphism of voluntary donors in Shenzhen Han population.Methods From January 2015 to December 2015,a total of 74 voluntary blood donors of Han nationality in Shenzhen Blood Center were selected into this study by simple random sampling method.Blood samples from all these donors were detected by urea solution hemolysis test of red blood cell and routine serological method,in order to identify the Kidd blood group phenotypes of donors.Genomic DNA covering exon 4-11 and partial introns of JK gene was amplified by PCR,and amplification products were directly sequenced.Results ① The Kidd blood phenotypes of 74 donors were 37 casesofJk (a+b+),16 casesofJk (a+b-),and 21 cases of Jk (a-b+).② Exon 4-5,exon 6,exon 7,exon 8-9,exon 10 and exon 11 of JK gene were successfully amplified from DNA samples of these 74 donors.③The JK gene of 37 samples of Jk (a+ b+) carried 2 kinds of heterozygous mutations,including exon 9 c.838G＞A and intron 7 c.664-68C＞T.The JK gene of 21 samples of Jk (a-b+) were homozygous for exon 9 c.838AA and intron 7 c.664-68TT,and 16 samples of Jk (a+b-) were homozygous for exon 9 c.838GG and intron 7 c.664-68CC.Intron 8 c.811+84TT was found in all 74 samples.Conclusions In the Kidd blood system of Shenzhen Han blood donors,the mutations of exon 9 c.838G＞A (p.Asp280Asn) and intron 7 c.664-68C＞T may be associated with JKa/JKb gene polymorphism.Homozygous genotypes for Intron 8 c.811 +84TT in JK gene were in all 74 blood donors,and homozygous for intron 8 c.811+84TT in JK gene is common allele in Shenzhen Han population.