湖北汉族人群T淋巴细胞免疫球蛋白黏蛋白-3基因单体型与变应性支气管哮喘的相关性

目的 分析湖北汉族人群T淋巴细胞免疫球蛋白黏蛋白-3(TIM-3)启动子区-1516G/T和外显子3区4259G/T单核苷酸多态性及其连锁不平衡关系,探讨其构成的单体型与支气管哮喘(简称哮喘)易感性之间的关系.方法 2004年6月至2007年10月采用等位基因特异性聚合酶链反应检测湖北汉族175例哮喘患者(哮喘组)和202名健康者(健康对照组)TIM-3-1516G/T和4259G/T的单核苷酸多态性,计算基因型和等位基因频率、两位点间的连锁不平衡系数(D')值及单体型频率.结果 TIM-3基因-1516G/T基因型GG、GT和TT在健康对照组中分布频率分别为82.7%(167/202)、17.3%(35/202)、0(0/202),哮喘组分布频率分别为82.9%(145/175)、17.1%(30/175)、0(0/175);TIM-3基因4259G/T基因型GG、GT和,TT在健康对照组中分布频率分别为0.5%(1/202)、2.5%(5/202)、97.0%(196/202),哮喘组分布频率分别为0.6%(1/175)、5.7%(10/175)、93.7%(164/175).对照组D'值为1.0,哮喘组D'值为0.9.湖北汉族人群中存在3种单体型(G-G、G-T、T-T),这3种单体型频率在健康对照组分别为1.7%(7/404)、89.6%(362/404)、8.7%(35/404),哮喘组分别为3.4%(12/350)、88.0%(308/350)、8.6%(30/350);3种单体型(G-G、G-T、T-T)与哮喘易感性无相关性(x2值分别为2.15、0.47、0.003,P均＞0.05).结论 TIM-3基因-1516G/T与4259G/T之间存在紧密连锁不平衡关系,G-G、G-T、T-T与哮喘易感性无相关性.但不排除是否与其他种族人群中哮喘易感性相关或与其他过敏性疾病和自身免疫性疾病的易感性相关.

The relationship between the haplotype of T cells immunoglobulin mucin-3 gene and allergic asthma in the Han population from Hubei province of China

OBJECTIVE: To investigate the single nucleotide polymorphisms (SNPs) of -1516G/T in the promoter region and 4259G/T in the exon-3 region of the T cells immunoglobulin mucin-3 (TIM-3) and their linkage disequilibrium, and therefore to detect their haplotype relationship with allergic asthma of the Han population from Hubei province of China. METHODS: The two polymorphisms were detected with allelic specific polymerase chain reaction (ASPCR). In the 175 asthmatic subjects and in the 202 healthy controls collected from June, 2004 to October 2007 in the Han population from Hubei province. The genotype and allele frequencies, the D' value between the two SNPs sites, the haplotype and their frequencies were calculated and analyzed, respectively. RESULTS: The genotype frequencies of GG, GT and TT in -1516G/T polymorphism of TIM-3 gene were 82.7% (167/202), 17.3% (35/202), 0 (0/202) respectively in the 202 controls, and 82.9% (145/175), 17.1% (30/175), 0 (0/175) respectively in the 175 asthmatic subjects. The genotype frequencies of GG, GT and TT in 4259G/T polymorphism of TIM-3 gene were 0.5% (1/202), 2.5% (5/202), 97.0% (196/202) respectively in the 202 controls and 0.6% (1/175), 5.7% (10/175), 93.7% (164/175) respectively in the 175 asthmatic subjects. The control group: D' = 1.0, the asthma group D' = 0. 9. The 3 haplotypes were G-G, G-T, T-T in the Han population from Hubei province of China, and their haplotype frequencies were distributed similarly in asthma 3.4% (12/350), 88.0% (308/ 350), 8.6% (30/350) and in the controls 1.7% (7/404), 89.6% (362/404), 8.7% (35/404). None of these differences were statistically significant (chi2 = 2.15, 0.47, 0.003 respectively, all P > 0.05). CONCLUSION: There are strong linkage disequilibrium between the two SNPs sites in TIM-3 gene in Han population from Hubei province, but the haplotypes G-G, G-T and T-T are not associated with asthma susceptibility of this population. We cannot exclude the possibility that the haplotypes of TIM-3 may be associated with asthma susceptibility in other ethnic populations or the susceptibility to other atopic diseases and autoimmunity diseases.