Genetic Disorders – Development
Kidney International (2000) 57, 401–404; doi:10.1046/j.1523-1755.2000.00859.x
Novel mutation in the nephrin gene of a Japanese patient with congenital nephrotic syndrome of the Finnish type
Kunihiko Aya, Hiroyuki Tanaka and Yoshiki Seino
Department of Pediatrics, Okayama University Medical School, Okayama, Japan
Received 6 May 1999; Revised 30 August 1999; Accepted 28 September 1999.
Abstract
Novel mutation in the nephrin gene of a Japanese patient with congenital nephrotic syndrome of the Finnish type.
Background
Congenital nephrotic syndrome (CNS) of the Finnish type is a rare autosomal-recessive disorder. Kestila et al reported that a positionally cloned gene for a novel glomerular protein nephrin is mutated in CNS. Most Finnish patients have one of two mutations. In this study, we described a Japanese CNS family associated with a novel missense point mutation in the nephrin gene.
Methods
Reverse transcription-polymerase chain reaction, polymerase chain reaction, and sequence analysis were used.
Results
The patient had the three missense mutations homozygously. One mutation was already reported as sequence variant. The two other novel mutations were the GAG to AAG transition, leading to a Glu447Lys and the GAC to GTC transition, predicting an Asp819Val substitution in the nephrin protein.
Conclusion
Our findings indicate that an abnormality of nephrin may cause CNS of the Finnish type in Japanese subjects.
Keywords:
Finnish congenital nephrotic syndrome, Japanese nephrotic syndrome, missense mutation, glomerular protein, gene mutation
