Глутаровая ацидурия типа 1 у детей. Клиническое представление 46 случаев, диагностированных в России

Background. Glutaric aciduria type 1 is an autosomal recessive disease caused by mutations in the GCDH gene, which encodes the enzyme glutaryl‑CoA dehydrogenase. Metabolic crisis in type 1 glutaric aciduria is an acute life‑threatening condition that requires careful diagnosis with a number of other conditions and the immediate initiation of pathogenetic therapy.Materials and methods. Clinical manifestations, neuroimaging characteristics of the disease were studied in 46 patients with diagnosed glutaric aciduria type 1 confirmed by biochemical and molecular genetic methods. Methods: gas chromatography with mass spectrometry, tandem mass spectrometry, Sanger sequencing, chromosomal microarray analysis of the exon level.Results and discussion. A retrospective analysis of anamnestic and clinical data was carried out, and the nature and age of disease manifestation, provoking factors, a spectrum of clinical manifestations and neuroimaging data were assessed.Conclusion. How initiated treatment prevents progression of neurological symptom relief and patient adaptation. With the help of the goal, it is necessary to inform pediatricians, neurologists and neuroradiologists about this feature of the course of glutaric aciduria type 1 in order to increase the clinical alertness of this disease.Введение. Глутаровая ацидурия типа 1 – аутосомно‑рецессивное заболевание, обусловленное мутациями в гене GCDH, кодирующем фермент глутарил‑КоА дегидрогеназу. Метаболический криз при глутаровой ацидурии типа 1 – это острое жизнеугрожающее состояние, требующее тщательной дифференциальной диагностики с рядом других состояний и незамедлительного начала патогенетической терапии.Материалы и методы. Клинические проявления, нейровизуализационные характеристики болезни изучены у 46 пациентов с подтвержденным биохимическими и молекулярно‑генетическими методами диагнозом глутаровой ацидурии типа 1. Методы: газовая хроматография с масс‑спектрометрией, тандемная масс‑спектрометрия, секвенирование по Сэнгеру, хромосомный микроматричный анализ экзонного уровня.Результаты и обсуждение. Проведен ретроспективный анализ анамнестических данных, клинических, а также оценены характер и возраст манифестации болезни, провоцирующие факторы, спектр клинических проявлений и нейровизуализационные данные.Заключение. При отсутствии массового неонатального скрининга крайне важное значение имеет ранняя диагностика болезни, так как своевременно начатое лечение поможет предотвратить прогрессирование неврологической симптоматики и способствовать адаптации пациентов. С этой целью необходимо информировать врачей‑педиатров, неврологов и нейрорадиологов об особенностях протекания глутаровой ацидурии типа 1 для повышения клинической настороженности в отношении данного заболевания

Genetic Variant c.245A>G (p.Asn82Ser) in GIPC3 Gene Is a Frequent Cause of Hereditary Nonsyndromic Sensorineural Hearing Loss in Chuvash Population

Hereditary nonsyndromic sensorineural hearing loss is a disease in which hearing loss occurs due to damage to the organ of the inner ear, the auditory nerve, or the center in the brain that is responsible for the perception of sound, characterized by wide locus and allelic heterogeneity and different types of inheritance. Given the diversity of population of the Russian Federation, it seems necessary to study the ethnic characteristics of the molecular causes of the disease. The aim is to study the molecular and genetic causes of hereditary sensorineural hearing loss in Chuvash, the fifth largest ethnic group in Russia. DNA samples of 26 patients from 21 unrelated Chuvash families from the Republic of Chuvashia, in whom the diagnosis of hereditary sensorineural hearing loss had been established, were analyzed using a combination of targeted Sanger sequencing, multiplex ligase-dependent probe amplification, and whole exome sequencing. The homozygous variant NM_133261.3(GIPC3):c.245A>G (p.Asn82Ser) is the major molecular cause of hereditary sensorineural hearing loss in 23% of Chuvash patients (OMIM #601869). Its frequency was 25% in patients and 1.1% in healthy Chuvash population. Genotyping of the NM_133261.3(GIPC3):c.245A>G (p.Asn82Ser) variant in five neighboring populations from the Volga-Ural region (Russian, Udmurt, Mary, Tatar, Bushkir) found no evidence that this variant is common in those populations

Monogenic diabetes associated with PAX4 gene mutations (MODY9): first description in Russia

Maturity-onset diabetes of the young (MODY) is a heterogeneous group of disorders characterised by autosomal dominant type of inheritance and caused by genetic defects leading to dysfunction of pancreatic beta-cells. To date, at least 13 subtypes of MODY have been described in the literature, the most frequent of which are MODY types 13. MODY2 and MODY3 are the most prevalent subtypes, and were previously described in our country, Russia. Several cases of rare MODY subtypes were subsequently described in the Russian literature. The current report is the first in the Russian literature to present clinical and molecular genetic characteristics of two cases of another rare MODY subtypeMODY9. This type of MODY is associated with mutations in the PAX4 gene, which encodes transcription factor PAX4, one of the factors essential for pancreatic beta-cell differentiation. Molecular genetic analysis was performed using next-generation sequencing, a new method recently applied to verify monogenic diseases and, in particular, MODY. This study reports a novel mutation in the PAX4 gene in MODY patients

Human hair growth deficiency is linked to a genetic defect in the phospholipase gene LIPH

The molecular mechanisms controlling human hair growth and scalp hair loss are poorly understood. By screening about 350,000 individuals in two populations from the Volga-Ural region of Russia, we identified a gene mutation in families who show an inherited form of hair loss and a hair growth defect. Affected individuals were homozygous for a deletion in the LIPH gene on chromosome 3q27, caused by short interspersed nuclear element-retrotransposon-mediated recombination. The LIPH gene is expressed in hair follicles and encodes a phospholipase called lipase H (alternatively known as membrane-associated phosphatidic acid-selective phospholipase A1alpha), an enzyme that regulates the production of bioactive lipids. These results suggest that lipase H participates in hair growth and development

Genetic analysis of autosomal recessive osteopetrosis in Chuvashiya: the unique splice site mutation in TCIRG1 gene spread by the founder effect

The rare malignant disorder autosomal recessive osteopetrosis (OPTB) is one of the most prevalent autosomal recessive diseases in the Chuvash Republic of Russia. The purpose of this study was to determine the underlying molecular cause of osteopetrosis in Chuvashiya and to reveal the factors causing the unusual high frequency of the disease in this region. Having assumed a founder effect, we performed linkage disequilibrium (LD) mapping of the OPTB locus at the TCIRG1 region and found a unique splice site mutation c.807+5G>A in all Chuvashian OPTB patients studied. We then analyzed the mutational change in mRNA and detected an intron insertion within the mutant transcript, resulting in a frameshift and premature stop-codon formation (p.Leu271AspfsX231). A decreased expression of the mutant transcript was also detected, which may have been the result of nonsense-mediated decay. Real-time qPCR and MLPA® melting curve analysis-based systems were designed and used for c.807+5G>A mutation screening. In addition to analyzing the gene frequency in Chuvashiya, we also estimated three other populations in the Volga-Ural region (Mari, Udmurt and Bashkir). We found a 1.68% prevalence in Chuvashiya (calculated disease frequency, 1/3500 newborns) and a 0.84% in the Mari population (1/14 000 newborns). The haplotype analysis revealed that all OPTB cases in Chuvashians and Marians originated from a single mutational event and the age of the mutation in Chuvashians was estimated to be approximately 890 years