<b>Conclusions:</b> Our data suggest that the p.N989I (c.2966A>T) variant of <i>MYPN</i> plays a dual role in hypertrophic cardiomyopathy pathogenesis, disrupting not only sarcomeric and cytoskeletal organization but also the regulation of the muscle gene program. This evidence concerns the gene MYPN and hypertrophic cardiomyopathy.