局灶节段性肾小球硬化患者致病基因突变检测

Detection of known causal mutations of FSGS in sporadic and familial focal segmental glomerulosclerosis

目的对散发性或家族性局灶节段性肾小球硬化（focal segmental glomerulosclerosis，FSGS）患者进行FSGS致病基因热点突变进行筛查，了解这些热点突变在我国FSGS患者的发生情况。方法研究对象为我院经肾脏活检确诊的40例FSGS散发病例及一个22人的FSGS家系LF-01。收集散发病例的外周血，采用盐析法提取基因组DNA；对LF-01家系进行调查，收集实验室检测数据，并留存外周血提取基因组DNA。对40例散发病例及所有家系成员进行ACTN4第8外显子，TRPC6第2、5、12、13外显子和INF2基因2、3、4外显子筛查，通过PCR扩增外显子后，直接测序进行基因突变检测。结果LF-01家系共9人为患病或可能患病状态，该家系表现为不完全外显遗传模型。40例散发FSGS患者，平均发病年龄37岁，男女比例为26：14，其中22例患者临床表现为肾病综合征。我们对所有样本进行了ACTN4第8外显子，TRPC6第2、5、12、13外显子和INF2基因2、3、4外显子筛查，均未发现有已知的基因突变。结论国外报道的FSGS致病基因的热点突变ACTN4、TRPC6和INF2可能不是中国汉族人群FSGS的致病基因。

Objective To detect the known causal mutations of FSGS in sporadic and familial focal segmental glomerulosclerosis （FSGS）. Methods Genomic DNA was extracted from peripheral whole blood cells of 40 sporadic patients and a FSGS family with 22 members. Polymerase chain reac tion（PCR） was used to amplify parts of extrons of ACTN4, TRPC6 and INF2 genes. The PCR products were purified and directly sequenced to determine whether any known causal mutation existed. Results This incompletely dominant inherited FSGS kindred included 22 members and 6 affected members. It was a late-onset family, and the mean age was 47. 3 years old on presentation. All the sporadic patients suffered in adolescence or adulthood with the mean age of 37 years old on presentation. All PCR products of ACTN4,TRPC6 and INF2 were directly sequenced and examined, and no mutation was found. Conclusions The already known pathogenic genes ACTN4, TRPC6 and INF2 were not the disease causing genes for this family and those sporadic patients with FSGS.