Department of Pediatrics, Hokkaido University School of Medicine, Sapporo, Japan.
Mutation analysis for five families with Wiskottt-Aldrich syndrome was performed. The mutations found were two missense mutations, two one-base deletion mutations, and a large deletion mutation in the WASP gene. The three mutations had been reported before, but the remaining two were new. We used the mutation information to determine the carrier status of the female relatives of the patients. Three different approaches were taken depending on the type of mutation, and the carrier determination was successfully performed.