Autosomal recessive Sorsby fundus dystrophy revisited: molecular evidence for dominant inheritance

Sorsby fundus dystrophy (SFD) originally was characterized as an autosomal dominant disorder in which patients lose central vision during the 4th or 5th decade of life. Since Sorsby's initial description, interfamilial phenotypic variations have been noted and have given rise to controversy as to whether SFD constitutes more than one nosologic entity. In addition, several reports have proposed the existence of a recessively inherited form of SFD. The recent identification of the tissue inhibitor of metalloproteinases-3 (TIMP3) as the disease-causing gene in SFD has made it possible to address the questions of clinical and genetic heterogeneity. In this study, we reinvestigated a large, highly consanguineous Finnish family previously diagnosed as having early-onset autosomal recessive SFD. We identified a novel heterozygous Gly166Cys mutation in TIMP3 in all affected individuals and provide strong evidence for an autosomal dominant inheritance of the SFD phenotype in this family. Our results, in conjunction with a critical review of the reported cases, render the existence of a recessive mode of inheritance in SFD questionable. Considering all available data, we suggest that SFD is a genetically homogeneous, autosomal dominant condition.