Introduction. The use of gene therapy in patients with spinal muscular atrophy (SMA) has led to a significant improvement in the prognosis of motor development. The inclusion of SMA in the expanded neonatal screening in the Russian Federation allowed not only identifying patients as early as possible, but also gene therapy at the presymptomatic stage of the disease became available for some of them.

Objective. To evaluate the effectiveness of gene therapy in real clinical practice during 2 years of follow-up of SMA patients treated with onasemnogen abeparvovec at the presymptomatic stage of the disease.

Materials and methods. The study included thirty five SMA children, with a genetically verified diagnosis of SMA without developing symptoms of the disease. The diagnosis of SMA was established during the pilot project of the extended neonatal screening or from 01/01/2023 as part of the extended neonatal screening. The diagnosis was verified during DNA diagnostics. Deletion of exons 7 and/or 8 of the SMN1 gene in the homozygous state was detected in all children. All patients received gene therapy with onasemnogen abeparvovec, the average age at the time of therapy was 2.00 ± 0.94 months (95% CI 1.68–2.32), min — 1.00, max — 5.00. A comprehensive assessment was conducted of clinical (the motor development milestones according to WHO, HINE-2 and CHOP-INTEND scores), electroneuromyographic (latency, amplitude and area of the negative peak of the compound muscle action potential during electrical stimulation of the ulnar nerve on the wrist; the motor nerve conduction velocity of the ulnar nerve on the forearm) and biochemical parameters (levels of light and heavy chains of neurofilaments (NF) in blood serum in SMA patients at the presymptomatic stage before initiation of gene therapy and after 6, 12, 18, and 24 months after its implementation.

Results. In our study, SMA patients at the presymptomatic stage, both before and after gene therapy, had motor development in accordance with age norms and did not significantly differ from children without neurological pathology. A comparative analysis of the electroneuromyographic parameters in SMA children and a group of healthy children revealed no statistically significant differences in patients at the presymptomatic stage of SMA on the background of gene therapy. A comparative analysis of the levels of light and heavy NF chains in the blood serum in SMA patients at the presymptomatic stage before gene therapy and 76 neurologically healthy children obtained in a recent study showed the level of light NF chains in SMA to be significantly higher (p < 0.001) — Me — 6.00, Q₁; Q₃ = 6.00; 31.43 pg/ml and Me — 4.00, Q₁; Q₃ = 2.50; 9.57 pg/ml, respectively. At the same time, the level of heavy NF chains did not significantly differ when comparing SMA patients at the presymptomatic stage before gene therapy with healthy peers. The use of onasemnogen abeparvovec in SMA patients at the presymptomatic stage led to a statistically significant decrease in the level of light chains NF in the blood serum. The maximum decrease in NF was observed 3–6 months after the gene therapy.

Conclusion. Carrying out gene therapy using the onasemnogen abeparvovek in SMA patients at the presymptomatic stage made it possible to prevent the development of symptoms of the disease and achieve the main stages of motor development milestones according to WHO criteria.

Compliance with ethical standards. Permission to conduct this study was obtained from the local ethics committee of the National Medical Research Center for Children’s Health (Minutes of the Local ethics committee, meeting No. 10 dated 10/06/2022).

Contribution:
Kuzenkova L.M., Kurenkov A.L., Uvakina E.V., Fisenko D.A. — concept and design of research, writing, editing;
Chernikov V.V. — statistical data processing, editing.
All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: November 6, 2024
Accepted: December 1, 2024
Published: January 31, 2025

Introduction. The dilated cardiomyopathy (DCM) represents a group of myocardial disorders whose primary characteristics are dilation of the left ventricular cavity and impaired systolic function. Thanks to significant progress in the field of molecular genetics, over fifty genes responsible for the primary form of DCM have now been identified, with mutations in the MYH7 gene accounting for up to 50% of all genetically confirmed cases. Objective: to establish the clinical and genetic characteristics of the dilated cardiomyopathy caused by mutations in the MYH7 gene in children.

Materials and Methods. This study analyzed data from 250 DCM children examined at the Cardiology department of the National Medical Research Center for Children’s Health of the Ministry of Health from 2015 to 2024. The investigation employed modern molecular genetic diagnostic methods and comprehensive clinical and instrumental examination, with assessment of clinical dynamics over a 5-year period.

Results. Isolated MYH7-associated DCM was confirmed in 80 (40,8%) unrelated children with identified causative variants. The clinical characteristics of the disease include early onset (over 80% of cases manifesting within the first year of life), frequent combination with non-compaction of the myocardium (85%), and the development of left ventricular reverse remodeling following treatment.Variants in exons 19–23 were established to be associated with severe mitral regurgitation, requiring surgical intervention at an early age. In 3 cases, a rare combination of cardiomyopathy and myopathy was observed.

Conclusion. The study confirms the significant role of pathogenic variants in the MYH7 gene in the development of cardiomyopathy in children. MYH7-associated forms of the disease with timely and appropriate drug therapy are characterized by a favorable prognosis, as evidenced by the high 5-year survival rate (97,4%) in patients. Molecular genetic testing is important in verifying the diagnosis, managing an early screening of relatives, and predicting the course of disease. The systematization of clinical and genetic characteristics creates the foundation for the devilment of personalized treatment approaches. A multidisciplinary approach to managing patients with cardiomyopathy and extracardiac manifestations is of particular importance.

Compliance with ethical standards. The study was conducted in accordance with the ethical standards of the Declaration of Helsinki of 1975 and was approved by the Local Ethics Committee of the National Medical Research Center for Children’s Health of the Ministry of Health of Russia (Protocol No. 10, dated August 28, 2020). Informed consent was obtained from all participants or their legal representatives.

Contribution:
Burykina Yu.S. — concept and design of the study, collection and processing of material, text editing;
Sdvigova N.A. — concept and design of the study, collection and processing of material, text editing;
Basargina E.N. — text editing;
Globa O.V. — text editing;
Kurenkov A.L. — text editing;
Zhanin I.S. — text editing;
Pushkov A.A. — collection and processing of material, text writing;
Savostyanov K.V. — concept and design of the study, text editing.

All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Acknowledgements. The authors express their gratitude to the patients’ families for supporting our research. The authors would like to express their gratitude to MD, Professor A.P. Fisenko, Director of the National Medical Research Center for Children’s Health of the Ministry of Health of the Russian Federation for his support and technical assistance in implementation of this work. The authors would like to thank the entire staff of the National Medical Research Center for Children’s Health of the Ministry of Health of the Russian Federation for the opportunity of interdisciplinary approach to patients care.

Received: October 8, 2025
Accepted: December 1, 2025
Published: January 31, 2026

Introduction. Spinal muscular atrophy (SMA) 5q is a progressive neuromuscular disorder caused by a mutation in the SMN1 gene. Pathogenetic therapy has significantly altered the natural course of the disease but has not ensured complete restoration of previously lost motor functions. Given the persistence of muscle weakness, rehabilitation remains a crucial component of comprehensive patient management. Objective of the study. To assess the volume and structure of rehabilitation in patients with SMA types 1–3 receiving pathogenetic therapy and determine its association with the trend in motor development based on the number of motor skills.

Materials and methods. The study included one hundred forty three patients with SMA types 1–3 (59 — SMA 1; 52 — SMA 2; 32 — SMA 3) aged of 0–18 years. The median time from the disease onset to the initiation of pathogenetic therapy was 6.0 [3.0; 13.0] months in SMA type 1, 45.0 [14.0; 90.0] months in SMA type 2, and 100.0 [67.0; 147.5] months in SMA type 3. The observation period was 3 years from the initiation of pathogenetic therapy. Functional status was assessed using eight motor skills according to WHO criteria. The volume of rehabilitation was determined through interviews and medical documentation. Statistical analysis was performed using SPSS Statistics, version 26.0 (IBM, USA).

Results. During pathogenetic therapy, patients with SMA type 1 demonstrated positive developmental course by the end of the follow-up period: head control increased from 35.6% to 82.5%, rolling from 1.7% to 67.5%, independent sitting was achieved in 75% of children, and 15% developed the ability to bear weight on their legs. In patients with SMA type 2, pathogenetic therapy resulted in stabilization of basic functions and a moderate increase in more complex motor skills (crawling improved from 12.5% to 17.4%; supported standing from 8.3% to 21.7%; assisted walking from 2.1% to 13%; independent walking — 7.9%). In the SMA type 3 group, motor progress on therapy was characterized mainly by preservation of existing skills with some improvements (e.g., an increase in the frequency of crawling to 42.9% and a single case of new-onset independent walking in a baseline “sitter”). In baseline “walkers” with SMA type 3, stabilization was observed. A significant association was identified between the number of acquired motor skills and the volume of rehabilitation in patients with SMA type 1, as well as in baseline “sitters” with SMA types 2 and 3 (p ≤ 0.014). In SMA type 1, regular comprehensive rehabilitation resulted in significantly higher motor skill scores compared with all other approaches (p_padj < 0.001). In SMA type 2, regular forms of rehabilitation (comprehensive or home-based) demonstrated advantages over course-based rehabilitation (p_padj ≤ 0.024). In the SMA type 3 group, among “sitters,” course-based rehabilitation during the year led to a better motor response to therapy compared with children receiving no rehabilitation (p_padj = 0.028).

Conclusions. Regular rehabilitation interventions, especially when combined with center-based rehabilitation courses, were associated with better motor responses to pathogenetic therapy in both SMA type 1 patients and baseline “sitters” with SMA types 2 and 3. These findings confirm the important role of continuous rehabilitation as part of the standard of care for SMA, serving as a necessary condition for achieving optimal motor progress under modern pathogenetic therapeutic approaches.

Compliance with ethical standards. The study was approved by the local ethics committee of the Pirogov Russian National Research Medical University (protocol No. 226 dated February 20, 2023).

Contributions:
Papina Yu.O — literature review, data collection and analysis, manuscript preparation, formulation of conclusions;
Stevanovich A.R. — literature review, manuscript preparation;
Melnik E.A. — manuscript editing, formulation of conclusions;
Artemyeva S.B. — study coordination;
Vlodavets D.V. — study coordination, manuscript editing.
All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: November 3, 2025
Accepted: December 1, 2025
Published: January 31, 2026

Introduction. Oxidative phosphorylation deficiency, type 10 is a rare variant of mitochondrial disease characterized by lactate acidosis, damage to the cardiovascular and central nervous systems. Given the variability of phenotype-genotypic correlations, a detailed description of the clinical picture of the disease is important for understanding possible variants of the course of the disease.

Materials and methods. During a molecular genetic study of three hundred fourteen pediatric patients with a guiding diagnosis of hypertrophic cardiomyopathy, one patient with a deficiency of oxidative phosphorylation, type 10, was identified.

Results. The analysis of the nature of the disease course during the period of dynamic follow-up (over 3 years) was carried out.

Conclusion. Deficiency of oxidative phosphorylation, type 10, is a rare cause of the hypertrophic phenotype of cardiomyopathy. Isolated cases of this disease have been described in the literature, which makes the observation significant for a wide range of specialists (pediatricians, neurologists, cardiologists).

Compliance with ethical standards. Voluntary informed consent was obtained from the patient’s legal representative for the publication of material related to the patient in Russian and foreign medical periodicals (dated October 1, 2024).

Contribution:
Shifova N.A. — concept and design of research, collection and processing of material, writing, editing;
Gandaeva L.A. — editing;
Globa O.V. — editing;
Silnova I.V. — editing;
Davydova Yu.I. — editing;
Basargina E.Y. — editing;
Savostyanov K.V. — the concept and design of the study.
All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: August 18, 2025
Accepted:September 30, 2025
Published: January 31, 2026

Introduction. Cardiomyopathy is the leading cause of mortality in dystrophinopathies. Standard screening methods often fail to detect early preclinical changes. The aim of the study was a comparative assessment of the diagnostic value of modern methods (global longitudinal strain — GLS, 24-hour ECG monitoring — Holter monitoring, myocardial damage biomarkers) in detecting early cardiac dysfunction.

Materials and methods. A prospective cross-sectional study included thirty one patient with Duchenne/Becker muscular dystrophy (DMD/BMD). All patients underwent comprehensive assessment including echocardiography with GLS analysis, 24-hour Holter monitoring, determination of NT-proBNP and troponin I levels.

Results. Reduced left ventricular ejection fraction (LVEF < 50%) was detected in 5 patients (16.1%). In patients with preserved LVEF, subclinical reduction in GLS was noted in 68.8%. Holter monitoring detected tachycardia significantly more often than a single ECG recording (p < 0.050), as well as a combination of tachycardia with reduced heart rate variability and high ventricular ectopic activity. The NT-proBNP level was significantly higher in the group with LVEF < 50% (279.8 [73.28; 844.8] vs. 60.83 [34.24; 104.5] pg/mL, p = 0.020).

Conclusion. Speckle-tracking echocardiography and 24-hour Holter monitoring have significantly higher sensitivity in detecting preclinical cardiomyopathy in DMD/BMD compared to standard screening. Their combined use with the determination of NT-proBNP and troponin I allows the risk stratificating and justifying early initiation of cardioprotective therapy.

Contributions:
Kaverina V.G. — writing the text;
Sdvigova N.A. — writing, editing the text;
Silnova I.V. — writing, editing the text;
Popovich S.G. — writing, editing the text;
Uvakina E.V. — writing, editing the text;
Basargina E.N. — conception and design of the article, writing the text, editing;
Kuzenkova L.M. — conception and design of the article, writing the text, editing.
All co-authors are responsible for the integrity of all parts of the manuscript and approval of its final version.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: December 1, 2025
Accepted: December 22, 2025
Published: January 31, 2026

Duchenne muscular dystrophy (DMD) is one of the most severe and common hereditary neuromuscular disorders characterized by progressive degeneration of muscle tissue, loss of motor function, and early mortality. Despite the availability of certain therapeutic options, disease outcomes largely depend on the timing of diagnosis and the initiation of clinical following-up. One of the most promising approaches to early detection is neonatal screening based on the measurement of creatine phosphokinase (CK) activity in dried blood spot samples, followed by genetic confirmation of the diagnosis. Numerous pilot newborn screening projects for DMD have been conducted worldwide using various analytical approaches, including fluorescent and immunofluorescent CK assays, as well as molecular genetic methods for diagnostic confirmation. This paper provides an overview of the history and current status of DMD screening programs in different countries, as well as key ethical and psychological aspects of presymptomatic diagnosis.

Contribution:
Voronin S.V. — concept and design, editing;
Mukhortova P.A. — writing the text, editing;
Slabikova A.A. — concept and design, writing the text, editing;
Omelyanovskiy V.V. — editing.
All co-authors — approval of the final version of the manuscript, responsibility for the integrity of all parts of the manuscript.

Funding. The study had no sponsorship.

Conflict of interest. The authors declare no conflict of interest.

Received: November 03, 2025
Accepted: December 01, 2025
Published: January 31, 2026