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We present a family with two male siblings diagnosed with a newly described digenic myopathy, involving likely pathogenic loss-of-function variants in the SRPK3 and TTN genes: hemizygous p.(Pro68ArgfsTer55) and heterozygous p.(Trp14174Ter), respectively. Both siblings experienced prenatal disease onset, characterized by weak fetal movements, but showed significant clinical improvement over two last years of our follow-up. Key features included early onset, delayed motor development, and prominent axial and proximal weakness, while adult variants' carriers remained asymptomatic, without any myopathic or cardiac manifestations. Lower limb MRI revealed distinctive abnormalities, with different patterns between the siblings: the older brother showed more pronounced involvement of the thigh muscles, while the younger brother exhibited greater changes in the lower leg muscles. Given the early stage of the disease in our patients and the initial changes observed on MRI, we suggest that the semitendinosus and vastus lateralis muscles are primarily involved at the thigh level in SRPK3/TTN-myopathy. This case highlights the importance of considering digenic inheritance in neuromuscular disorders and underscores the necessity of comprehensive genetic analysis in similar cases., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Limb-girdle muscular dystrophies (LGMD) constitute a heterogeneous group of genetic disorders characterized by progressive muscle weakness and atrophy, predominantly affecting the muscles of the pelvic and shoulder girdles. LGMD R27, linked to biallelic pathogenic variants in the JAG2 gene, was recently described, and to date, only 27 cases has been published in three reports. Here, we present two siblings exhibiting a severe clinical phenotype of LGMD R27, associated with a novel JAG2 homozygous frameshift variant [c.3467_3470dup, p.(Pro1158AlafsTer22)] results in truncated protein with 21 amino acid substitution within the cytoplasmic domain of the Jagged2 protein., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Nikitin, Melnik, Sharkova, Murtazina, Shchagina, Zabnenkova, Tsargush, Dadali and Kutsev.)

Sarcoglycanopathies encompass four distinct forms of limb-girdle muscular dystrophies (LGMD), denoted as LGMD R3-R6, arising from mutations within the SGCA, SGCB, SGCG, and SGCD genes. The global prevalence of sarcoglycanopathies is low, making it challenging to study these diseases. The principal objective of this study was to explore the spectrum of mutations in a cohort of Russian patients with sarcoglycanopathies and to ascertain the frequency of these conditions in the Russian Federation. We conducted a retrospective analysis of clinical and molecular genetic data from 49 Russian patients with sarcoglycan genes variants. The results indicated that variants in the SGCA gene were found in 71.4% of cases, with SGCB and SGCG genes each exhibiting variants in 12.2 % of patients. SGCD gene variants were detected in 4.1% of cases. Bi-allelic pathogenic and likely pathogenic variants were identified in 46 of the 49 cases of sarcoglycanopathies: LGMD R3 (n = 34), LGMD R4 (n = 4), LGMD R5 (n = 6), and LGMD R6 (n = 2). A total of 31 distinct variants were identified, comprising 25 previously reported and 6 novel variants. Two major variants, c.229C>T and c.271G>A, were detected within the SGCA, constituting 61.4% of all mutant alleles in Russian patients with LGMD R3. Both LGMD R6 cases were caused by the homozygous nonsense variant c.493C>T p.(Arg165Ter) in the SGCD gene. The incidence of sarcoglycanopathies in the Russian Federation was estimated to be at least 1 in 4,115,039, which is lower than the reported incidence in other populations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The article presents results of primary researches of information field of non-profit medical organizations in Russia, carried out from January 01 to December 31 2019 in Yandex search engine and Medialogia media database. The analysis of results of the study with measurements of beginning and end of 2019 was carried out. The results are one of parts of a panel study of image of medical non-profit organizations in Russia and can be used in future by interested structures with purpose of its adjustment.

Congenital myasthenic syndrome with episodic apnea is associated with pathogenic variants in the CHAT gene. While respiratory disorders and oculomotor findings are commonly reported in affected individuals, a subset of patients only present with muscle weakness and/or ptosis but not apneic crises. In this case series, we describe five individuals with exercise intolerance caused by single nucleotide variants in the CHAT gene. The age of onset ranged from 1 to 2.5 years, and all patients exhibited a fluctuating course of congenital myasthenic syndrome without disease progression over several years. Notably, these patients maintained a normal neurological status, except for the presence of abnormal fatigability in their leg muscles following prolonged physical activity. We conducted a modified protocol of repetitive nerve stimulation on the peroneal nerve, revealing an increased decrement in amplitude and area of compound muscle action potentials of the tibialis anterior muscle after 15-20 min of exercise. Treatment with 3,4-diaminopyridine showed clear improvement in two children, while one patient experienced severe adverse effects and is currently receiving a combination of Salbutamol Syrup and pyridostigmine with slight positive effects. Based on our findings and previous cases of early childhood onset with muscle fatigability as the sole manifestation, we propose the existence of a mild phenotype characterized by the absence of apneic episodes., Competing Interests: AS is employed by Genomed Ltd., Russia. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Murtazina, Borovikov, Marakhonov, Sharkov, Sharkova, Mirzoyan, Kulikova, Ganieva, Zabnenkova, Ryzhkova, Nikitin, Dadali and Kutsev.)

In this study, we report a novel splice variant in the TRA2B gene identified in a patient presenting with seizures and neurodevelopmental delay. This paper represents the second investigation of pathogenic variants in the TRA2B gene in humans, reaffirming the conclusions of the initial study and underscoring the importance of this research. Comprehensive genetic testing, including whole genome sequencing, Sanger sequencing, and mRNA analysis, was performed on the proband and her parents. The proband harbored a de novo c.170+1G>A variant in the RS1 domain of Tra2β, which was confirmed to be pathogenic through mRNA analysis, resulting in exon 2 deletion and a frameshift (p.Glu13Valfs*2). The clinical presentation of the patient was consistent with phenotypes described in one of the previous studies. These findings contribute to the dissemination and reinforcement of prior discoveries in the context of TRA2B -related syndrome and highlight the need for further investigation into the functional consequences and underlying pathogenic mechanisms associated with TRA2B mutations.

The article contains the results of primary research of the information field of medical tourism in Russia, conducted in the period before the COVID-19 pandemic in the Yandex search engine and the Medialogia media database from January 01, 2019 to December 31, 2019. The analysis of the results of the study with measurements of the beginning of the year and the end is carried out. The results of the study are one of the parts of the panel study of the image of medical tourism in Russia and can be used in the future by interested structures in order to adjust it.

We present a patient with unusual episodes of muscular weakness due to homozygous deletion of exon 2 in the MICU1 gene. Forty-three patients from 33 families were previously described with homozygous and compound heterozygous, predominantly loss of function (LoF) variants in the MICU1 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. Our patient had a few severe acute episodes of muscle weakness with minimal myopathy features between episodes and a strongly elevated Creatinine Kinase (CK). Whole exome sequencing (WES) was performed and the homozygous deletion of exon 2 was suspected. To validate the diagnosis, we performed an RNA analysis of all family members. To investigate the possible impact of this deletion on the phenotype, we predicted a new Kozak sequence in exon 4 that could lead to the formation of a truncated MICU1 protein that could partly interact with MCU protein in a mitochondrial Ca 2+ complex. We suspect that this unusual phenotype of the proband with MICU1-related myopathy could be explained by the presence of the truncated but partly functional protein. This work helps to define the clinical polymorphism of MICU1 deficiency better., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Sharova, Skoblov, Dadali, Demina, Shchagina, Konovalov, Ampleeva, Sharkova and Kutsev.)

GNE myopathy (GNEM) is a rare hereditary disease, but at the same time, it is the most common distal myopathy in several countries due to a founder effect of some pathogenic variants in the GNE gene. We collected the largest cohort of patients with GNEM from Russia and analyzed their mutational spectrum and clinical data. In our cohort, 10 novel variants were found, including 2 frameshift variants and 2 large deletions. One novel missense variant c.169_170delGCinsTT (p.(Ala57Phe)) was detected in 4 families in a homozygous state and in 3 unrelated patients in a compound heterozygous state. It was the second most frequent variant in our cohort. All families with this novel frequent variant were non-consanguineous and originated from the 3 neighboring areas in the European part of Russia. The clinical picture of the patients carrying this novel variant was typical, but the severity of clinical manifestation differed significantly. In our study, we reported two atypical cases expanding the phenotypic spectrum of GNEM. One female patient had severe quadriceps atrophy, hand joint contractures, keloid scars, and non-classical pattern on leg muscle magnetic resonance imaging, which was more similar to atypical collagenopathy rather than GNEM. Another patient initially had been observed with spinal muscular atrophy due to asymmetric atrophy of hand muscles and results of electromyography. The peculiar pattern of muscle involvement on magnetic resonance imaging consisted of pronounced changes in the posterior thigh muscle group with relatively spared muscles of the lower legs, apart from the soleus muscles. Different variants in the GNE gene were found in both atypical cases. Thus, our data expand the mutational and clinical spectrum of GNEM.

The article contains the results of repeated studies of the Russian healthcare information field conducted during the third wave of COVID-19 in the Medialogia media database, as well as in the Yandex search engine from May 20, 2021 to September 01, 2021. There was carried out a comparative analysis of the results of the study with previous measurements conducted from December 01, 2019 to February 15, 2021. The results of the study are just a part of the image panel study of the Russian healthcare and they can further be used by concerned structures in order to adjust it.

The article presents the results of restudy of the Russian health care information field, carried out during the second wave of COVID-19 in the mass media database "Medialogia" and in the search engine "Yandex" from October 1, 2020 to January 31, 2021. The comparative analysis of the results of the study with previous measurements taken from December 1, 2019 to May 15, 2020 was implemented. The results of the study are a portion of panel study of the Russian health care system image and can be used hereinafter by interested structures with the view of its adjustment.

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. Data of over 14000 whole exome sequencing analyses was used to calculate the estimated disease frequency. RNA analysis was performed by RT-PCR. QSVanalyzer software was used to quantify the allelic disbalance., Results: We describe the clinical and molecular characterizations of 17 patients with MPAN. DNA analysis detected three previously undescribed pathogenic/likely pathogenic variants in the C19orf12 gene. The estimated disease frequency was calculated to be 1:619150. We describe unusual clinical observations in several cases. One patient showed severe neurogenic muscle weakness along with a lack of marked spasticity or optic nerve atrophy. In another mild clinical case with the NM_001031726.3:c.204_214del (p.(Gly69Argfs*10)) variant in a heterozygous state, a marked allelic disbalance was observed on the RNA level with reduced expression level of the wild-type allele. Thus, this case became the first one of a possible regulatory variant causing MPAN., Conclusion: We reported a detailed clinical and molecular characterization of the third-largest MPAN cohort. We expanded the mutational and clinical spectrum of MPAN. Moreover, we calculated the estimated MPAN frequency in the Russian population for the first time., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The article represents the results of a studying the information field of the healthcare sector in Russia. Measurements were made in the Yandex search engine, as well as in the Medialogia media database. The study was conducted between December 01, 2019 and may 15, 2020. The results of the studying are one part of the studying of the image of Russian healthcare and may be necessary for further work on its correction.

Neurodegeneration with brain iron accumulation type 4 (NBIA4) also known as MPAN (mitochondria protein-associated neurodegeneration) is a rare neurological disorder which main feature is brain iron accumulation most frequently in the globus pallidus and substantia nigra. Whole exome sequencing (WES) in a 12-year-old patient revealed 2 variants in the C19orf12 gene, a previously reported common 11 bp deletion c.204_214del11, p.(Gly69Argfs*10) and a novel splicing variant c.193+5G>A. Functional analysis of novel variant showed skipping of the second exon, resulting in a formation of a truncated nonfunctional protein. This is the first functionally annotated pathogenic splicing variant in NBIA4.

Data of own researches and the review of the literary data for studying pathogenesis and features of HMSN, type 1 Х caused by mutations in gene GJB1 are presented in this paper. X-linked HMSN is the genetic variant second for frequency in Russian, it constitute 22% from total of patients of this group. Features of this genetic variant are considerable distinction in weight clinical displays at patients man's and female. It is shown that at the majority of female patients clinical displays are expressed less, and at 20% were absent at all. The assumption is come out that at indicators of CNV from 35 to 52 m/s, it is necessary to conduct research in gene GJB1 especially at patients of a female and as to carry out search of mutations at all relatives with HMSN, type 1 X even in the absence of complaints from their party.

Seventy four patients with clinical presentation of LGMD and probably autosomal-recessive type of inheritance were examined. Five different mutations of FKRP gene responsible for LGMD2 type I were detected in eight (10.8%) patients. Two of them с.341C>G, c.826C>A were described before and three c.229C>T, с.265C>T, с.1078G>C were found for the first time. The significant clinical polymorphism due to the difference in age of manifestation and severity of clinical presentation was identified.