Mutation hot spots in the 5p31-linked corneal dystrophies

Mutations in the BIGH3 gene on chromosome 5q31 cause 4 distinct autosomal dominant human cornea diseases characterized by accumulation of corneal deposits in a progressive fashion and in time by loss of vision. A specific recurrent missense mutation for each type of dystrophy is in 10 independently ascertained families. Genotype analysis with microsatellite markers around BIGH3 has been carried out for the 10 families and in 5 families reported in the past. New data imply that R555W, H124H and R124C mutations were independent in a number of ethnic groups. Apparently the mutations don't reflect a putative founder effect. The specific importance of the R124 and R555 amino acids in the pathogenesis of autosomal dominant corneal dystrophies linked to 5p has been confirmed.