中国胰岛素依赖性糖尿病病人（HLA－DR9）的HLA－DQB1基因顺序分析

Sequencing of HLA-DQB1 Gene Second Exons in Chinese HLA-DR9 Insulin Dependant Diabetes Mellitus Patients

用血清学方法研究显示中国人胰岛素依赖性糖尿病（ＩＤＤＭ）与ＨＬＡ－ＤＲ９相关。鉴于白种人中的研究显示ＩＤＤＭ与ＨＬＡ－ＤＱβ链第５７位氨基酸相关，Ａｓｐ－５７对ＩＤＤＭ呈抗性，ｎｏｎ－Ａｓｐ与ＩＤＤＭ易感性相关。我们用ＰＣＲ技术扩增了中国人中血清学ＤＲ９纯合的ＩＤＤＭ患者和正常对照的ＨＬＡ－ＤＱＢ１基因第二外显子并测定了核苷酸顺序，结果未发现ＩＤＤＭ特异ＨＬＡ－ＤＱＢ１等位基因，但发现ＩＤＤＭ病人ＨＬＡ－ＤＱＢ１５７位均为天冬氨酸。表明中国ＩＤＤＭ患者中的ＨＬＡ－ＤＱＢ１５７位天冬氨酸不一定具有保护个体抵抗ＩＤＤＭ的足够能力。ＩＤＤＭ易感性可能涉及多个基因位点的变化，另外还可能与其它遗传因素及环境因素有关。

The serological analysis showed that HLA-DR9 was strongly associated with insulin dependant diabetes mellitus(IDDM)in Chinese.The studies of Caucasian IDDM have found that amino acid residue 57 of HLA-DQ chain correlates strongly with IDDM.Here,the polymerase chain reaction was used to amplify HLA-DQBI gene second exons of 2 Chinese HLA-DR9 IDDM patients and 2 normal controls.The PCR products were then cloned and the nucleotide sequences were determined by dideoxy termination method.No unique IDDM related HLA-DQB1 allele was found. However,Asp-57 encoding HLA-DQB1 alleles were found in both IDDM patients,indicating that Asp-57 may not be resistant to IDDM in Chinese.IDDM susceptibility is polygenic in inheritance and may be influenced by other genetic or environmental factors.