CH Wang, JH Mao, XL Ma, LP Shi

Abstract

Background: NPHS1 mutation is one of the major causes of congenital nephrotic syndrome (CNS). Studies have confirmed that approximately one-half of CNS cases are caused by recessive mutations in NPHS1. In China, there have been a few reports of NPHS1 mutation in infants with CNS which indicates NPHS1 may be the causative gene in sporadic Chinese CNS. In this study, NPHS1 mutations in a Chinese family with CNS were detected and analysed. Methods: A five-day-old male infant suffered generalised oedema, proteinuria, hypoproteinaemia, and hypoalbuminaemia. His kidney histology showed characteristics of CNS. Mutation analysis was made of all exons and exon/intron boundaries of NPHS1 in the infant and his parents using polymerase chain reaction and direct DNA sequencing. Results: Two compound heterozygous mutations, including 1019C>T (P340L) in exon 9 and 3478C>T (R1160Stop) in exon 27, were identified in the infant with CNS. Only 1019C>T (P340L) was identified in mother and 3478C>T (R1160Stop) in father respectively. Conclusions: These findings reconfirm that NPHS1 gene mutations also present in sporadic Chinese CNS cases. Genetic studies of NPHS1 gene should be performed in young infant with CNS for genetic counselling.