RESUMO
Objective To elucidate the mutations of NPHS1 gene in children with sporadic steroid-resistant nephrotic syndrome (SRNS) in Southern Chinese Han ethnic group.Methods Peripheral blood samples were collected for genetic analysis from 40 patients with sporadic SRNS and 50 healthy volunteers as control.Genomic DNA was isolated from peripheral blood leucocytes.Twenty-nine exons and exon-intron boundaries of the NPHS1 gene were amplified by polymerase chain reaction.Mutational analysis was performed by DNA sequencing directly.Results Seven variants,928G＞A(D310N),2677A＞G (T893A),2869G＞C (V957L),IVS8+30C＞T,IVS21+14G＞A,IVS25-23C＞T and *142T＞C,of NPHS1 gene were found in 6 of 40 children with sporadic SRNS,whereas they were not found in 50 healthy controls.2677A ＞G,IVS8 +30C ＞T,IVS21 +14G＞A,IVS25-23C ＞T and *142T＞C were novel.Moreover,thirteen already reported NPHS1 polymorphisms,294C＞T,349G＞A,IVS3+15C＞T,IVS3+61A＞G,803G＞A,IVS8+68A＞G,1339G ＞A,1802G ＞C,2223C ＞T,2289C ＞T,IVS24 +36C ＞T,3315G＞A and IVS27 +45C ＞T,were detected in some patients and controls. Conclusions NPHS1 mutations in 6 of 40 children with sporadic SRNS in Southern Chinese Han ethnic group (15％) are detected.NPHS1 mutations are existed in Southern Chinese children,so it is necessary to perform the mutation analysis of NPHS1 gene in those children patients.