Fatal Infantile Cardiomyopathy Associated with a Homozygous MYL2 c.413T>A (p.Met138Lys) Variant: A Case Expanding the Recessive MYL2 Phenotypic Spectrum

BACKGROUND/OBJECTIVES: -related cardiomyopathy. METHODS: We report a male infant with congenital hypotonia and delayed motor development who underwent extensive metabolic, neuromuscular, and neuroimaging evaluation. Trio-based whole-exome sequencing was performed to identify a potential genetic etiology, followed by variant interpretation using standard bioinformatic and ACMG/AMP criteria. RESULTS: -associated disease, these findings support a likely pathogenic interpretation. CONCLUSIONS: -associated cardiomyopathy and highlights the value of early genomic testing in infants with unexplained hypotonia and rapidly progressive cardiac dysfunction. Molecular diagnosis may aid in prognosis, clinical decision-making, and genetic counseling.