中国汉族儿童散发性激素耐药型肾病综合征CD2AP基因突变分析

Mutational analysis of CD2AP in children with sporadic steroid-resistant nephrotic syndrome in Chinese Han ethnic group

目的分析中国汉族散发性激素耐药型肾病综合征(SRNS)患儿CD2AP基因突变及其特点。方法40例中国汉族散发性SRNS患儿,以及50例尿检正常的汉族成年人,取外周静脉血3 ml,提取基因组DNA,应用聚合酶链反应(PCR)方法扩增CD2AP基因全部18个外显子及其周围的部分内含子,进行直接DNA序列测定。应用神经网络程序对CD2AP基因内含子突变进行隐蔽性剪接位点预测。结果在40例散发性SRNS患儿中检测出11种CD2AP基因多态性,并在3例散发性SRNS患儿中检测出3种在正常对照人群中未发现的CD2AP基因变异,IVS7-135G>A、1083T>C和IVS13-137G>A。神经网络程序分析结果结合临床表型提示,IVS7-135G>A突变为非致病突变、1083T>C和IVS13-137G>A突变的致病性不明确。结论中国汉族散发性SRNS患儿存在CD2AP基因突变,今后尚需对CD2AP基因突变与SRNS患儿临床表型的关联性进行详尽研究。

Objective To examine genetic variations of CD2AP in children with sporadic steroid-resistant nephrotic syndrome （SRNS） in Chinese Han ethnic group. Methods Peripheral blood samples were collected for genetic analysis from forty children with sporadic SRNS in Chinese Hart ethnic group and 50 healthy volunteers of the worrnal eontorl group. Genomic DNA was isolated from peripheral blood leucocytes. Eighteen exons and exon-intron boundaries of the CD2AP gene were amplified by polymerase chain reaction. Mutational analysis was performed by direct DNA sequencing directly. Intron variations were evaluated for potential splice sites using the neural networks program Genie. Results Eleven polymorphisms of CD2AP were found in 40 patients with sporadic SRNS. Three types of mutation of CD2AP （IVS7-135G 〉 A, 1083T 〉 C and IVS13-137G 〉 A） were detected in three of the forty children with sporadic SRNS, whereas they were not found in 50 controls. However, assessed by combination of neural networks program Genie and clinical phenotype IVS7-135G 〉 A was a non-causative mutation, while the pathogenicity of 1083T 〉 C and IVS13- 137G 〉 A remained elusive. Conclusions Our results indicate that CD2AP mutations exist in the children with sporadic SRNS in Chinese Han ethnic group. It suggests that extendsive analysis of correlation between mutations in the CD2AP gene and clinical phenotypes in children with sporadic SRNS is necessary.