Clinical manifestations of familial exudative vitreoretinopathy in children with nucleotide sequence alterations in the FZD4 gene

Abstract

Familial exudative vitreoretinopathy (FEVR)is a rare genetically heterogeneous disease with multiple types of inheritance (autosomal dominant, autosomal recessive, X-linked) and widely varying clinical features. Up to 40 % of cases of FEVR are associated with mutations of the FZD4 gene.Purpose: to investigate the clinical manifestations of FEVR in children with nucleotide sequence alterations in the FZD4 gene. Material and methods. The Helmholtz National Medical ResearchCenter of Eye Diseases and the ResearchCentre for MedicalGenetics conducted a joint in-depth ophthalmological examination of 18 patients aged from 3 weeks to 17 years with a diagnosis of FEVR, which included a detailed ophthalmoscopy under drug mydriasis, ultrasound and electrophysiological examination, photographic recording of fundus changes using RetCam and Fundus Foto. Molecular genetic examination was carried out by direct sequencing according to Sanger. Results. Nucleotide sequence alterations in the FZD4 gene were detected in 3 patients(16.7 %)from two unrelated families. In one family, a 12-year-old girl wasfound to display the firstsymptoms of ophthalmic pathology (reduced vision, strabismus) at the age of 3.5 years. In another family, the clinical manifestations of FZD4 gene mutations were observed in two children during the first year of life (at the age of 5 and 11 months).Conclusions. The clinical picture of 3 patients with detected changes in the nucleotide sequence of the FZD4 gene is characterized by early manifestation and bilateral asymmetric ophthalmoscopic damage. The results of the study indicate the need for a timely diagnosis of FEVR in young children, recommend an interdisciplinary approach to the study of the disease, which should contribute to a better understanding of pathogenesis, and the development of an effective diagnostic, treatment and rehabilitation algorithm.