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Updated: Jan 8, 2026

Measuring Connectivity in the Primary Visual Pathway in Human Albinism Using Diffusion Tensor Imaging and Tractography
Published on: August 11, 2016
Genetic Features of Albinism: A Comprehensive Analysis in the Russian Population
Sofya Ionova1, Andrey Marakhonov1, Vitaliy Kadyshev1
1Research Centre for Medical Genetics, Moscow, Russia.
Abstract:
We present a comprehensive molecular and epidemiological analysis of albinism in a Russian cohort, comprising 177 probands with isolated (OCA1, OCA2, OCA3, OCA4, and OA) and syndromic (HPS-associated) forms of the disease. The comparative analysis of population frequencies between the National Genetic Initiative "100,000 + Me" (NGI) project and GnomAD (v3.1.2) revealed variants in the TYR gene (NM_000372.5):c.650G>A and c.1037-7 T>A, which are specifically prevalent in the Russian population. The functional analysis was provided for variants in the TYR gene, which can probably affect splicing. Based on the population frequency in the NGI project, we calculated the minimal estimated disease frequencies for isolated forms of albinism. Using molecular genetic results, functional analysis, and ACMG classification, the diagnosis was confirmed in 71.8% (127/177) of the cases in the Russian cohort.
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