Bardi R, Ju L Y, Jenhani S, Ayed K, Chammakhi S, Charron D
Laboratoire d'Immunologie, Faculté de Médecine de Tunis, Tunisia.
Res Immunol. 1991 Mar-Apr;142(3):211-6. doi: 10.1016/0923-2494(91)90060-v.
HLA class II antigens are transmembrane glycosylated heterodimers composed of an alpha and a beta chain. Several of these chains are highly polymorphic. The structural bases of the polymorphism are nucleotide acid substitutions which are situated in the first domain (exon II) of alpha and beta genes. Specific sequences of these domains can be obtained by amplification of genomic DNA using the polymerase chain reaction. Polymorphic sites are recognized by restriction endonuclease treatment and separation of the DNA fragments by polyacrylamide gel electrophoresis. The resulting fragments of different lengths are used to identify different alleles. We used the above technique for typing the HLA-DQA1 alleles in 41 Tunisian diabetic patients. The frequency of DQA10301 was greatly increased compared with the control group. This was in agreement with previously published data in Caucasian and Japanese insulin-dependent diabetes mellitus (IDDM) patients, while the significant increase in the frequency of the DQA10501 allele was comparable with that of Caucasian IDDM patients but contrasted with a decrease in this allele in Japanese IDDM patients. Our results provide confirmation of the contribution of the DQA1*0301 allele to disease susceptibility in a Tunisian population.
人类白细胞抗原（HLA）II类抗原是由一条α链和一条β链组成的跨膜糖基化异二聚体。其中几条链具有高度多态性。这种多态性的结构基础是位于α和β基因第一个结构域（外显子II）的核苷酸替换。这些结构域的特定序列可通过聚合酶链反应扩增基因组DNA获得。多态性位点通过限制性内切酶处理和聚丙烯酰胺凝胶电泳分离DNA片段来识别。由此产生的不同长度的片段用于鉴定不同的等位基因。我们使用上述技术对41名突尼斯糖尿病患者的HLA - DQA1等位基因进行分型。与对照组相比，DQA10301的频率显著增加。这与先前发表的关于白种人和日本胰岛素依赖型糖尿病（IDDM）患者的数据一致，而DQA10501等位基因频率的显著增加与白种人IDDM患者相当，但与日本IDDM患者中该等位基因频率的下降形成对比。我们的结果证实了DQA1*0301等位基因对突尼斯人群疾病易感性的影响。
