常染色体显性成人多囊肾病两家系PKD1、PKD2基因的突变鉴定

目的 鉴定两个常染色体显性成人多囊肾病家系的致病突变.方法 采用酚氯仿法提取家系成员及无亲缘关系的100名健康对照个体的外周血白细胞DNA,PCR扩增先证者致病基因PKD1、PKD2的所有外显子序列及其侧翼内含子剪切区域,直接测序确定DNA序列的变异.通过家系和正常对照的比较分析,对检测到的变异是否与疾病相关进行了初步探讨.结果 在两个家系中共检测到5个序列变异:PKD1:c.2469G＞A,PKD1:c.5014_5015 delAG,PKD1:c.10529C＞T,PKD2:c.568G＞A和PKD2:c.2020-1_2020 delAG.其中PKD1:c.2469G＞A和PKD2:c.2020-1_2020 delAG为新发现的变异.此外,检测到的移码突变和剪切突变未见于家系中健康成员及无亲缘关系的正常对照.结论 PKD1:c.5014_5015 delAG和PKD2:c.2020-1_2020 delAG分别为家系A和B的致病突变,且PKD2:c.2020-1_2020 delAG为先证者新发生的突变.

Identification of mutations in PKD1 and PKD2 genes in two Chinese families with autosomal dominant polycystic kidney disease

Objective To identify the responsible mutation of autosomal dominant polycystic kidney disease (ADPKD) in two Chinese families.Methods Total genomic DNA of all available family members and 100 unrelated healthy controls was extracted from peripheral blood leukocytes using a standard phenol-chloroform procedure. All exons with intronic flanking sequences of the PKD1 and PKD2 genes in the probands were amplified by PCR.Mutations were detected directly by DNA sequencing.To evaluate the pathogenicity of the variations,family and control based analyses were performed.Results Five sequence variants were identified in the two families including PKD1:c.2469G＞A,PKD1:c.5014_5015delAG,PKD1:c.10529C＞T,PKD2:c.568G＞A and PKD2:c.2020-1_2020delAG.Among them,PKD1:c.2469G＞ A and PKD2:c.2020-1 _ 2020 delAG were novel mutations. Furthermore,the frameshift and splicing site mutations detected in the affected individuals were not detected in their unaffected relatives and 100 unrelated normal controls.Conclusion PKD1:c.5014_5015delAG and PKD2:c.2020-1_2020delAG are the responsible mutations of family A and B,respectively,and PKD2:c.2020-1_2020delAG is a de novo mutation.