Common Variants in the Gene with Unclear Pathogenicity as the Cause of Oculocutaneous Albinism in a Cohort of Russian Patients.

oculocutaneous albinism (OCA) is a hereditary impairment of skin, hair, and eye pigmentation. The most common form of albinism is autosomal recessive albinism, caused by mutations in the gene, accounting for approximately 40-50% of all cases of the disease in European populations. Common hypomorphic variants in the gene could lead to a mild form of albinism in a compound heterozygous state with a pathogenic variant.

GABRA1-Related Disorders: From Genetic to Functional Pathways.

Objective: Variants in GABRA1 have been associated with a broad epilepsy spectrum, ranging from genetic generalized epilepsies to developmental and epileptic encephalopathies. However, our understanding of what determines the phenotype severity and best treatment options remains inadequate. We therefore aimed to analyze the electroclinical features and the functional effects of GABRA1 variants to establish genotype-phenotype correlations.

Clinical Characterization of Alagille Syndrome in Patients with Cholestatic Liver Disease.

Alagille syndrome (ALGS) is a multisystem condition characterized by cholestasis and bile duct paucity on liver biopsy and variable involvement of the heart, skeleton, eyes, kidneys, and face and caused by pathogenic variants in the or gene. The variable expressivity of the clinical phenotype and the lack of genotype-phenotype correlations lead to significant diagnostic difficulties. Here we present an analysis of 18 patients with cholestasis who were diagnosed with ALGS.

Case report: Unusual episodic myopathy in a patient with novel homozygous deletion of first coding exon of gene.

We present a patient with unusual episodes of muscular weakness due to homozygous deletion of exon 2 in the gene. Forty-three patients from 33 families were previously described with homozygous and compound heterozygous, predominantly loss of function (LoF) variants in the gene that lead to autosomal recessive myopathy with extrapyramidal signs. Most described patients developed muscle weakness and elevated CK levels, and half of the patients had progressive extrapyramidal signs and learning disabilities.

Complex Diagnostics of Non-Specific Intellectual Developmental Disorder.

Intellectual development disorder (IDD) is characterized by a general deficit in intellectual and adaptive functioning. In recent years, there has been a growing interest in studying the genetic structure of IDD. Of particular difficulty are patients with non-specific IDD, for whom it is impossible to establish a clinical diagnosis without complex genetic diagnostics.

The First Russian Patient with Native American Myopathy.

Congenital myopathy associated with pathogenic variants in the gene has long been considered native American myopathy (NAM). In 2017, the first case of a non-Amerindian patient with this myopathy was described. Here, we report the first Russian patient with NAM.

mRNA analysis revealed a novel pathogenic EIF2S3 variant causing MEHMO syndrome.

EIF2S3 pathogenic variants have been shown to cause MEHMO syndrome - a rare X-linked intellectual disability syndrome. In most cases, DNA diagnostics of MEHMO syndrome is performed using exome sequencing. We describe two cousins with profound intellectual disability, severe microcephaly, microgenitalism, hypoglycemia, epileptic seizures, and hypertrichosis, whose clinical symptoms allowed us to suspect MEHMO syndrome.

A Two-Year Clinical Description of a Patient with a Rare Type of Low-GGT Cholestasis Caused by a Novel Variant of .

Here, we report a novel truncating mutation in the ubiquitin-specific peptidase gene () causing low-γ-GT (GGT) cholestasis. Genetic testing was carried out, including clinical exome sequencing for the proband and Sanger sequencing for the proband and his parents. The proband harbored a novel c.

Retrospective analysis of 17 patients with mitochondrial membrane protein-associated neurodegeneration diagnosed in Russia.

Introduction: Mitochondrial membrane protein-associated neurodegeneration (MPAN) is a rare neurological syndrome caused by pathogenic variants in the C19orf12 and is characterized by iron deposition in the basal ganglia and substantia nigra. Only a limited number of cohort studies were published to date and the prevalence of MPAN remains uncertain.

Methods: Recruited subjects with MPAN in Russia were diagnosed by whole-exome sequencing or Sanger sequencing of the C19orf12 gene.