A 2ND FAMILY WITH XLRH DISPLAYS THE MUTATION-S244L IN THE CLCN5 GENE

Mutations in the CLCN5 gene, mapped in Xp11.22, have been recently rep orted to be associated with X-Linked nephrolithiasis, X-linked recessi ve hypophosphataemic rickets and Dent's disease. We report a missense mutation in exon 6 of the CLCN5 gene. The mutation in this pedigree is S244L, the same mutation as has previously been described in an Itali an family showing a similar pathology. However, in the family reported here, affected males have developed neither nephrolithiasis nor nephr ocalcinosis. The question arises whether we are dealing with a milder phenotype or whether a more severe pathology will develop with ageing.