[Molecular diagnosis of mutations responsible for recurrent and severe forms of primary congenital glaucoma]

A PCR-based test has been developed that makes it possible to detect a G to A substitution in the cytochrome P4501B1 gene. This mutation brings about a substitution of glutamic acid to lysine in the cytochrome P4501B1 molecule, and has been shown to be responsible, in homozygous form, for a severe and prognostically unfavourable form of primary congenital glaucoma (PCG). This type of PCG has been previously demonstrated to be extremely frequent in the population of Gypsies (Roms) in Slovakia. In this study, all 33 PCG Gypsy patients examined were found homozygous for this particular mutation, and among 101 unrelated healthy screened subjects from the Gypsy ethnic community, almost 14% of mutation carriers were identified. The test sugesed here makes it possible to perform a direct DNA-based prenatal diagnosis of PCG in the families at risk, as well as to screen for gene carriers.