The relevance of genetic counseling in various forms of hereditary retinal dystrophies

Abstract

Purpose. Retrospective genetic counseling analysis of patients with hereditary retinal diseases. Material and methods. The study is based on an analysis of genetic counseling and molecular genetic studies of DNA samples of 82 patients: Stargardt disease (n=37), Fundus Flavimaculatus (n=34), Best vitelliform macular dystrophy (n=11). All patients had a comprehensive ophthalmologic clinical and functional examination. Geneticist physician conducted a genealogical analysis. Search for mutations at each clinical form of the disease was carried out after a verification of clinical and genetic disease forms. The exons and flanking intronic regions were studied using methods of analysis of amplified fragment length polymorphism, restriction fragments and direct sequencing. Results . The searched pathogenic mutations were identified in pro-bands in 46% of cases in patients with a clinical diagnosis of Stargardt disease and in both of family members aimed at analyzing. Mutations were not detected in the ELOVL4 gene. One  or more pathogenic mutations in probands with Fundus Flavimaculatus were revealed in 46% of cases. Diagnosis of Best vitelliform macular dystrophy was molecular genetically confirmed in 8 patients. The results of genetic counseling of patients with hereditary diseases of the retina, as well as members of their  families showed a clinical and genetic diversity and difficulties in the diagnosis of this group of diseases in Russia. Conclusion. Complex clinical, functional and molecular genetic testing all members of proband’s family allows to increase the rate of detection in carriers of pathogenic mutations without any clinical appearance of the disease. Identification of the most frequent mutations in different genetic ophthalmic pathology in patients of the Russian Federation allows to create the «DNA panel» for genetic studies, which increase an availability of such studies for the population, as well as lead to a speedy implementation of screening methods of DNA diagnosis i n the practical healthcare.