目的分析和确定Gitelman综合征相关基因SLC12A3突变位点,以提高对该病的认识和理解。方法通过直接测序的方法寻找和确定12例Gitelman综合征患者相关基因SLC12A3的突变位点。选取50例健康正常人作为对照,评估发现的突变位点。结果共确定SLC12A3基因8个突变位点,其中5个为新突变位点,包括2个错义突变:Cys430Gly和Leu571Pro;2个缺失突变:1384delG和346~353delACTGATGG;1个非移码插入突变: 997insCys。3个已报道过的突变,其中包括2个错义突变:Thr60Met和Asp486Asn;1个缺失突变:2883-2884delAG。12例患者中8例携带Thr60Met纯合或杂合突变,大部分患者为复合杂合突变。结论基因突变分析对诊断Gitelman综合征有重要价值。Thr60Met可能是中国Gitelman综合征患者较常见的突变。Gitelman综合征特异的表型和基因型之间的联系目前较难确定。
Objective To analyze and identify the mutations of SLC12A3 gene in Gitelman syndrome patients, and improve the cognition and apprehension to the disease. Methods Twelve patients [8 males and 4 females, age (37±13) years] hospitalized in Ruijin hospital from 7 unrelated families with the clinical and biochemical features of Gitelman syndrome were analyzed by direct sequencing of SLC12A3 gene. Fifty unrelated normal subjects were selected to evaluate all the mutations found by this study. Results Eight mutations were identified in SLC12A3 gene of 12 patients with Gitelman syndrome. Five were novel variants, including 2 missense mutations: Cys430Gly and Leu571Pro; two deletions: 1384delG and 346-353delACTGATGG; and one in-frame insertion: 997insCys. Three were recurrent ones including two missense mutations: Thr60Met and Asp486Asn, and one deletion: 2883-2884delAG. The homozygous or heterozygous mutation Thr60Met was found in 8 of 12 patients. The majority of the patients were compound heterozygotes. Conclusion Gene analysis is essential to diagnose Gitelman syndrome. Thr60Met may be a more common mutation in Chinese patients with Gitelman syndrome. Possible specific genotype-phenotype correlation is difficult to identify.