组织相容性复合物DQ基因与胰岛素依赖型糖尿病易感相关性剂量效应规律的研究

为研究中国北方汉族人中组织相容性复合物ＤＱ（ＨＬＡ－ＤＱ）基因与胰岛素依赖型糖尿病（ＩＤＤＭ）遗传易感性相关的剂量效应规律，采用聚合酶链反应和序列特异性寡核苷酸探针杂交技术，对５４例胰岛素依赖型糖尿病患儿和４０例正常成年供血员ＨＬＡ－ＤＱ基因进行了研究。结果：携带４个易感性基因的个体只见于患者，携带３个易感性基因的个体在患者中为３３．３％，正常对照中为１０％；携带２个或１个易感性或保护性基因的个体在正常对照中频率较患者为高，但差异无显著意义；携带３个保护性基因的个体只见于正常对照。提示：ＩＤＤＭ易感性基因具有部分隐性遗传的特点且具有累加效应。个体中１个或２个易感性基因的存在不能对ＩＤＤＭ构成显著的易感性，３个或３个以上易感性基因的存在方可对ＩＤＤＭ构成显著易感性。ＤＱ保护性基因具有部分显性遗传的特点并且也具有累加效应。携带１个或２个保护性基因的个体患ＩＤＤＭ的机会将大大减少，而携带３个保护性基因的个体则可以不发生ＩＤＤＭ。

A study on dose effect rules of the relationship between human leukocyte antigen DQ alleles and genetic susceptibility of insulin dependent diabetes mellitus

To study the dose effect rules in IDDM genetic susceptibility contributed by human leukocyte antigen DQ (HLA DQ) alleles, the authors applied polymerase chain reaction and sequence specific oligonucleotide probe dot blot hybridization techniques to classify the HLA DQ alleles of 54 children with IDDM and 40 normal controls. The results indicated that the individuals with 4 susceptive alleles could be found only in the patients, the number of individuals with 3 susceptive alleles was significantly increased in the patients than in controls (33.3% vs 10%), while the frequency of the individual with 1 or 2 susceptive or protective alleles was a little higher in controls than in the patients, and the individuals carrying 3 protective alleles could only be seen in controls. These results suggest that the effect of susceptive alleles is somewhat recessive and could be accumulated. The individual with one or two susceptive alleles might not offer significant predisposition to IDDM, while the individuals with three or more susceptive ones could be associated with significant susceptibility. The effect of protective alleles is parfially predominant. The individual carrying one or two protective alleles could contribute certain protection to IDDM, while those with three protective ones might have complete resistance to IDDM.