Gyrate atrophy is a hereditary chorioretinal degeneration associated with a deficiency of ornithine aminotransferase (OAT). By means of a complementary DNA clone encoding human OAT, the OAT gene sequences were mapped by somatic cell hybrids and in situ hybridization to human chromosome regions 10q26 and Xp11.2. A review of 80 biochemically confirmed cases of gyrate atrophy confirmed the autosom...