内蒙古汉族儿童过敏性紫癜与HLA-DQA1基因的关联性研究

Correlation between HLA-DQA1 allele and anaphylactoid purpura in juvenile Hans residing in Inner Mongolia

目的 探讨内蒙古汉族儿童 HL A- DQA1等位基因与过敏性紫癜 (anaphylactoid purpura,AP)的遗传易感性及其与临床特点的关系。方法 用聚合酶链反应 -序列特异性引物技术 ,对 70例内蒙古汉族儿童 AP和 90名健康儿童 HL A- DQA1等位基因进行对比分析。结果 (1)病例组 DQA1* 0 30 1基因频率为 33.4% ,明显高于对照组 (10 .6 % ) (P<0 .0 1) ;DQA1* 0 30 2基因频率为 6 .7% ,明显低于对照组(19% ) (P<0 .0 1)。 (2 )单纯皮肤紫癜病例组与对照组 DQA1* 0 30 1和 0 30 2基因频率比较 ,差异无显著性(P>0 .0 5 ) ;伴有胃肠、关节、肾脏损害病例 DQA1* 0 30 1基因频率分别为 2 6 .7%、2 8.5 %和 2 9.3% ,均明显高于对照组 (10 .6 % ) (P均 <0 .0 1) ;而 DQA1* 0 30 2基因频率分别为 3.9%、5 .7%和 9.6 % ,分别与对照组 (19% )比较 ,肾脏损害组差异无显著性 (P>0 .0 5 ) ,胃肠和关节损害组均明显降低 (P均 <0 .0 1)。结论HL A- DQA1* 0 30 1等位基因可能是内蒙古汉族儿童 AP发病单体型中一个遗传易感基因 ,具此基因者可能更易出现胃肠、关节和肾脏损害 ;而 DQA1* 0 30 2等位基因可能为其遗传保护基因 ,对出现胃肠、关节损害可能有拮抗作用。

Objective. To analyze the genetic susceptibility of HLA-DQA1 allele to anaphylactoid purpura (AP) and its association with the clinical features in juvenile Hans residing in Inner Mongolia. Methods. Seventy children with AP and ninety normal controls of Hans in Inner Mongolia were subjected to HLA-DQA1 genotyping with the use of polymerase chain reaction-sequence specific primer (PCR-SSP) technique. Results. (1) The gene frequency of HLA-DQA1 * 0301 of AP group (33.4%) was significantly higher than that (10.6%) of control group (X2=21. 899, P2= 9. 786, P 0. 05). The gene frequencies of DQA1 * 0301 of the cutaneous purpura cases associated with gastrointestinal, joint and renal impairment were 26.7%, 28.5% and 29.3% respectively, which were higher than that of the control group (10. 6%); the differences were statistically significant (P < 0. 01, 0. 01, 0.01; respectively). The gene frequencies of HLA-DQA1 * 0302 (3.9%, 5.7% and 9.6%) for the cutaneous purpura cases associated with gastrointestinal, joint and renal impairment were significantly lower than that (19%) of the controls except renal impairment(P < 0.01, 0. 01,respectively). Conclusion. The allele of HLA-DQA1 * 0301 was probably a susceptible gene while HLA - DQA 1 * 0 3 0 2 was the protective one in AP of the children who were Han inhabitants in Inner Mongolia. The results of this study also revealed that patients with the allele of HLA-DQA1 * 0301 tended to involve gastrointestinal, joint and renal impairment.