The first diagnostics of the syndrome «renal dysplasia with retinal degeneration» (Senior-Loken syndrome1) based on the NGS technology in the Russian Federation

Abstract

Aim: to clarify the diagnosis using a thorough study of the clinical picture and molecular genetic diagnostic methods in a complex clinical case of a combination of retinal pathology and kidney disease.
Methods. A 17-year-old patient with a presumptive diagnosis of retinal dystrophy had a complete clinical examination, including laboratory and instrumental studies. Сlinical exome sequencing by NGS (next-generation sequencing).
Results. The patient was diagnosed with retinal hypoplasia, normal motor and psychomotor development, stage 2 chronic kidney disease, small kidney cysts and morphological changes characteristic of nephronophthisis1. A deletion of the entire NPHP1 gene in a homozygous state was detected, which allowed for differential diagnosis with diseases with similar clinical manifestations and confirmed the diagnosis of Senior-Loken syndrome 1 in the patient. Analysis of segregation revealed that the mother carried the same deletion in a heterozygous state while the father was not available for analysis.
Conclusion. For successful diagnostics of hereditary diseases with significant genetic heterogeneity, it is necessary to use NGS methods. To confirm deletions and establish the exact boundaries of the rearrangement, it is necessary to conduct whole-genome sequencing.