A MUTATION IN THE NORRIE DISEASE GENE (NDP) ASSOCIATED WITH X-LINKED FAMILIAL EXUDATIVE VITREORETINOPATHY

Familial exudative vitreoretinopathy (FEVR) is a hereditary disorder c haracterized by an abnormality of the peripheral retina. Both autosoma l dominant (adFEVR) and X-linked (XLFEVR) forms have been described, b ut the biochemical defect(s) underlying the symptoms are unknown. Mole cular analysis of the Norrie gene locus (NDP) in a four generation FEV R family (shown previously to exhibit linkage to the X-chromosome mark ers DXS228 and MAOA (Xp11.4-p11.3)) reveals a missense mutation in the highly conserved region of the NDP gene, which caused a neutral amino acid substitution (Leu124Phe), was detected in all of the affected ma les, but not in the unaffected family members, nor in normal controls. The observations suggest that phenotypes of both XLFEVR and Norrie di sease can result from mutations in the same gene.