Current aspects and approaches to molecular diagnostics of hereditary neuromuscular diseases

Relevance. The problem of diagnosing hereditary neuromuscular diseases is one of the most difficult in the medical specialists’ practice. Molecular genetic diagnostics is one of the fundamental aspects in the classification and subsequent approaches to the treatment and prevention of hereditary diseases. Pathogenic variants identification leads to the formation of separate subtypes and phenotypically identical diseases syndromes. This review examines modern diagnostic methods and algorithmization of patients with neuromuscular diseases. Despite enormous research and clinical efforts, the molecular causes remain unknown for almost half of patients with neuromuscular diseases due to genetic heterogeneity and molecular diagnostics based on a gene-by-gene approach. Next-generation sequencing (NGS) is an effective and cost-effective strategy for accelerating patient diagnosis. However, the diagnostic value of conducting and prescribing whole- exome or whole- genome sequencing is largely dependent on the clinical picture of the disease and the professional competence of the doctor. Hereditary neuromuscular diseases have similar initial symptoms, and molecular genetic diagnostics can pinpoint the cause and pathogenesis of the observed disorders in the patient. Conclusion . The molecular diagnostics algorithm is based on sequential analysis, starting with the search for the most common pathogenic variants using inexpensive and rapid methods, and progressing to the search for rare, previously undescribed pathogenic variants using whole-g enome/whole-exome studies. The phasing allows science and medicine to uncover previously unknown causes of severe disease in patients with neuromuscular diseases, which often leading to disability or premature death. Earlier genetic diagnosis should provide more effective treatment of the disease and better genetic counseling for families and will also allow access to pathogenetic therapy for neuromuscular diseases.