Open AccessNeuronal ceroid lipofuscinosis in the Russian population: Two novel mutations and the prevalence of heterozygous carriers
Author(s) -
Kozina Anastasiya A.,
Okuneva Elena G.,
Baryshnikova Natalia V.,
Kondakova Olga B.,
Nikolaeva Ekaterina A.,
Fedoniuk Inessa D.,
Mikhailova Svetlana V.,
Krasnenko Anna Y.,
Stetsenko Ivan F.,
Plotnikov Nikolay A.,
Klimchuk Olesia I.,
Popov Yaroslav V.,
Surkova Ekaterina I.,
Shatalov Peter A.,
Rakitko Alexander S.,
Ilinsky Valery V.
Publication year - 2020
Publication title -
molecular genetics and genomic medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.765
H-Index - 29
ISSN - 2324-9269
DOI - 10.1002/mgg3.1228
Subject(s) - neuronal ceroid lipofuscinosis , frameshift mutation , genetics , missense mutation , exome sequencing , population , allele , biology , genotype , compound heterozygosity , mutation , phenotype , gene , medicine , environmental health
Abstract Background Neuronal ceroid lipofuscinoses (NCLs) are a group of neurodegenerative disorders characterized by an accumulation of lipofuscin in the body's tissues. NCLs are associated with variable age of onset and progressive symptoms including seizures, psychomotor decline, and loss of vision. Methods We describe the clinical and molecular characteristics of four Russian patients with NCL (one female and three males, with ages ranging from 4 to 5 years). The clinical features of these patients include cognitive and motor deterioration, seizures, stereotypies, and magnetic resonance imaging signs of brain atrophy. Exome sequencing was performed to identify the genetic variants of patients with NCL. Additionally, we tested 6,396 healthy Russians for NCL alleles. Results We identified five distinct mutations in four NCL‐associated genes of which two mutations are novel. These include a novel homozygous frameshift mutation in the CLN6 gene, a compound heterozygous missense mutation in the KCTD7 gene, and previously known mutations in KCTD7 , TPP1 , and MFSD8 genes. Furthermore, we estimated the Russian population carrier frequency of pathogenic and likely pathogenic variants in 13 genes associated with different types of NCL. Conclusion Our study expands the spectrum of mutations in lipofuscinosis. This is the first study to describe the molecular basis of NCLs in Russia and has profound and numerous clinical implications for diagnosis, genetic counseling, genotype–phenotype correlations, and prognosis.