Features of the genetic diagnosis of merosin-deficient muscular dystrophy (a clinical case)

Merosin-deficient muscular dystrophy is a rare neuromuscular disease characterized by diffuse muscular and epileptic seizures. The disease is inherited in an autosomal recessive type and occurs as a result of biallelic variants in the LAMA2 gene. In this gene there are described all types of violations of the normal nucleotide sequence (single nucleotide variants, variations in the number of DNA copies) which can lead to difficulties in genetic search. The combination of phenotype features (hypomimia, elongated face, ophthalmoparesis, muscle hypotonia, and weakness, spinal rigidity, contractures of large joints), laboratory and instrumental research results (increased activity of creatinephosphokinase in the blood, leukopathy on brain MRI) will help you choose the right diagnostic search tactics. In this article, we present a clinical case of a patient with three identified variants in the LAMA2 gene: two point substitutions (c.4048C>T and c.4860+75G>C) and deletion of exons 2 and 3. The use of several methods of genetic testing (high-throughput sequencing, chromosomal microarray analysis, Sanger sequencing) allowed the establishing of the diagnosis, which subsequently led to successful prenatal diagnosis and the birth of healthy siblings.

Contribution:
Monakhova A.V. — writing text;
Vlodavets D.V. — concept, editing;
Kanivets I.V. — editing.
All co-authors — approval of the final version of the manuscript, responsibility for the integrity of all parts of the manuscript.

Acknowledgements. The study had no sponsorship.

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

Received: November 13, 2024
Accepted: November 11, 2024
Published: January 31, 2024

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