汉族慢性肾衰竭儿童6例NPHS2和WT1基因遗传学变异

Genetic Variations of NPHS2 and WT1 Genes in 6 Children with Chronic Renal Failure in Chinese Han Ethnic Group

目的分析汉族慢性肾衰竭(CRF)儿童NPHS2和WT1基因遗传学变异及其特点。方法研究对象为6例汉族CRF儿童和50例尿检正常的汉族成年人。分别取其外周静脉血3mL,提取基因组DNA。应用PCR方法扩增NPHS2和WT1基因的全部8个外显子及其周围的部分内含子。通过DNA直接测序法和限制性片段长度多态性/PCR分析法对NPHS2和WT1基因进行遗传学变异分析。结果未发现NPHS2和WT1基因致病突变,但检测到2个NPHS2基因多态性(102G>A和954T>C)和4个WT1基因变异(5′-UTR-7G>T、126C>T、IVS5-9T>C和903A>G)。NPHS2基因多态性(102G>A)在6例CRF儿童与对照人群中的基因型频率和等位基因频率比较均无显著性差异(Pa>0.05)。3个WT1基因变异(5′-UTR-7G>T、126C>T和903A>G)在100条正常染色体中也有检出,其在6例CRF儿童与对照人群中的基因型频率和等位基因频率比较均无显著性差异(Pa>0.05)。1个WT1基因变异(IVS5-9T>C)在1例患儿及其父亲(尿检正常)中检出,为杂合变异,而在100条正常染色体中未检出。结论IVS5-9T>C为新发现的WT1基因变异,NPHS2和WT1基因突变不是本研究6例汉族CRF儿童的主要致病原因。

ObjectiveTo analyze genetic variations of NPHS2 and WT1 genes in children with chronic renal failure（CRF） in Chinese Han ethnic group.MethodsPeripheral blood samples were collected for genetic analysis from 6 children with CRF,and 50 unrelated adult volunteers in Chinese Han ethnic group whose urinalysis were normal studied as controls.Genomic DNA was isolated from peripheral blood leucocytes.Eight exons and exon-intron boundaries of NPHS2 gene,and 8 exons and exon-intron boundaries of WT1 gene were amplified by polymerase chain reaction（PCR）.Mutational analysis was performed by DNA sequencing directly and restriction fragment length polymorphism/PCR.ResultsNo mutation in both NPHS2 gene and WT1 gene was detected in 6 children with CRF,whereas 2 already reported polymorphisms of NPHS2 gene,102G〉A and 954T〉C,and 4 variants of WT1 gene,5＇-UTR-7G〉T,126C〉T,IVS5-9T〉C and 903A〉G,were identified in some of the patients.Three variants of WT,（5＇-UTR-7G〉T,126C〉T and 903A〉G） were also identified in some controls.There was no significant difference in the genotypic and allelic frequencies of 102G〉A of NPHS2 gene,and 5＇-UTR-7G〉T,126C〉T and 903A〉G of WT1 gene between the 6 children and 50 controls,respectively.In addition,a novel variant,IVS5-9T〉C of WT1 was identified in 1 child and his father whose urinalysis was normal,whereas it was not found in 50 controls.ConclusionsIVS5-9 T〉C of WT1 gene is a novel heterozygous variant.Mutations in both NPHS2 gene and WT1 gene are not major causes of the 6 children with CRF in the study.