Road to a Genetic Model of Gelatinous Drop-Like Corneal Dystrophy

Gelatinous drop-like corneal dystrophy (GDLD; OMIM: 204870) is an autosomal recessive Mendelian-inherited disease. Subepithelial amyloid deposition results in severe visual impairment. Its pathogenesis remains unknown. Identification of the responsible gene is a useful approach to investigating the pathogenesis of genetic diseases. Such an identification is also necessary for the creation of genetic models. For this purpose, our group performed positional cloning using homozygosity mapping. The results revealed that GDLD maps to the short arm of chromosome 1. Subsequent mutation analyses identified tumor-associated calcium signal transducer 2 (TACSTD2; former name, M1S1) as the gene responsible for GDLD. After identification of the gene, we examined the phylogenetical distribution of TACSTD2 in the genomes of vertebrates.