染色体显性遗传性多囊肾病PKD2基因突变的检测

Detection of PKD2 Gene Mutation in Chromosomal Dominant Polycystic Kidney Disease

目的:建立检测常染色体显性遗传性多囊肾病2型(polycystic kidney disease 2,PKD2)致病基因突变的方法,检测收集的10个ADPKD家系共15例患者的PKD2基因突变情况。方法:收集江西地区经临床确诊的常染色体显性遗传性多囊肾病患者15例,采集外周静脉血5 mL,用试剂盒提取基因组DNA,采用聚合酶链式反应(PCR)扩增PKD2基因全部外显子及相近内含子区域,PCR扩增产物经分离纯化后直接进行基因序列测序,根据测序图谱进行突变分析,明确基因突变位点和类型。结果:15例常染色体显性遗传性多囊肾病(autosomal dominant polycystic kidney disease,ADPKD)患者中,检测出3个正常基因多态性位点,分别为1号外显子第420位碱基G置换为A,未引起编码氨基酸改变;1号外显子第568位碱基G置换为A,致使190位编码氨基酸由丙氨酸改变为苏氨酸;内含子靠近cDNA第844位碱基5’端的第22个碱基A置换为G。结论:可通过直接基因序列测定对PKD2进行基因突变检测,本研究所检测到的3个正常基因多态性位点均已有报道,为开展ADPKD直接基因诊断、产前诊断及症状前诊断提供了实验基础。

Objective:To set up a method for detecting the mutations of autosomal dominant olycystic kidney disease gene 2,detect the mutations of PKD2 in 15 patients from 10 ADPKD families.Method:Fifteen patients with autosomal dominant polycystic kidney disease diagnosed clinically in Jiangxi were collected,5 mL peripheral venous blood was collected and genomic DNA was extracted with the kit.All exons and close intron regions of PKD2 gene were amplified by polymerase chain reaction(PCR),after isolation and purification,PCR amplification products were directly sequenced,and mutation analysis was conducted according to the sequencing map to identify the mutation sites and types of genes.Result:Three polymorphisms were detected in 15 ADPKD patients.The c.568 G>A in exon1 caused the translation change(Ala190 Thr).The other two(c.420 G>A in exon1 and 844-22 A>G in IVS3)did not cause the translation change.Conclusion:Gene mutation detection of PKD2 can be performed by direct gene sequencing,all the 3 normal gene polymorphisms detected in this study have been reported,providing an experimental basis for direct gene diagnosis,prenatal diagnosis and pre-symptom diagnosis of ADPKD.