Genetic background of Fuchs' heterochromic cyclitis.

We studied the genetic background of 24 patients with Fuchs' heterochromic cyclitis (FHC). Each was given a careful eye examination which included family history and serological determination of HLA antigens. Two families each had 2 cases of FHC in the same family; in addition an ancestor in the second family possibly had FHC; in both families one healthy member had simple heterochromia. One patient with FHC had congenital uveal coloboma, one pigmentary retinal dystrophy, and four had cysts of the ciliary body. The frequencies of all HLA antigens in patients with FHC compared well with the frequencies in the controls. In a family in which HLA haplotypes could be derived, the patients with FHC showed different HLA haplotypes. We conclude that FHC has a hereditary basis but its immunological component is not genetically associated with the HLA system.