不完全川崎病患儿遗传易感性研究

Genetic susceptibility in children with incomplete Kawasaki disease

摘要:

目的 分析2 个与川崎病(Kawasaki disease, KD)相关的基因CD40 基因及BLK 基因位点在不完全KD 中的单核苷酸多态性(SNP)分布特点,并探讨其与不完全KD 的遗传易感性以及临床表型的相关性。方法 采用病例对照研究方法,选取184 例不完全KD 患儿和203 例体检正常儿童作为研究对象。利用限制性片段长度多态性分析的方法测定CD40 基因及BLK 基因SNP 位点多态性分布,比较两组其SNP 位点基因型分布,并分析其基因多态性与不完全KD 临床特点的相关性。结果 患儿CD40 基因SNP 位点(rs1569723)的3 种基因型(AA,AC,CC)频率及等位基因频率与对照组相比差异均无统计学意义。BLK 基因SNP 位点(rs2736340)的基因型频率与对照组相比差异有统计学意义(P=0.031),且KD 组T 等位基因频率明显高于对照组(P=0.007)。CD40 基因SNP 位点(rs1569723)3 种不同基因型患儿结膜充血的比例差异有统计学意义(P=0.036);而BLK基因中SNP 位点(rs2736340)的多态性与患儿四肢末端改变相关(P=0.017)。结论 BLK 基因SNP 位点(rs2736340)与不完全KD 的易感性相关;BLK 基因SNP 位点(rs2736340)及CD40 基因SNP 位点(rs1569723)多态性与部分临床表型相关。

Abstract:

Objective To study the frequency distribution of single nucleotide polymorphisms (SNPs) in two genes associated with incomplete Kawasaki disease (KD) (rs1569723 in CD40 gene and rs2736340 in BLK gene), and to investigate its association with the genetic susceptibility and clinical phenotypes of incomplete KD. Methods A total of 184 children with incomplete KD and 203 normal children were recruited to carry out a case-control study. The genotypes of SNPs in CD40 gene and BLK gene were determined using polymerase chain reaction-restriction fragment length polymorphism. The frequency distribution of genotypes was compared between the KD and control groups. The association between gene polymorphisms and clinical features of incomplete KD was analyzed. Results There were no significant differences in genotype (AA, AC, CC) and allele frequencies in CD40 SNP rs1569723 between the KD and control groups. There were significant differences in the frequency distribution of three genotypes (TT, CT, CC) in BLK SNP rs2736340 between the KD and control groups (P=0.031), and the KD group had a significantly higher frequency of T allele than the control group (P=0.007). There were significant differences in the incidence of conjunctival hyperaemia among the patients with different genotypes (rs1569723 in CD40 gene) (P=0.036). The SNP rs2736340 in BLK gene was associated with the extremity changes in KD patients (P=0.017). Conclusions The SNP rs2736340 in BLK gene is associated with the susceptibility to incomplete KD, and the SNP rs1569723 in CD40 gene and SNP rs2736340 in BLK gene are associated with some of clinical phenotypes of incomplete KD.