Hypertrophic Cardiomyopathy Mutation R723G in MYH7 Enhances Its mRNA‐Stability

Allelic imbalance describes the unequal expression of a gene's two alleles. Whereas it has no effect under normal circum-stances, it can aggravate disease course in patients with heterozygous mutations. Hypertrophic cardiomyopathy (HCM), the most common inherited cardiac disorder, is mostly caused by heterozygous mutations in different sarcomeric proteins. One of the most commonly affected proteins is the β-myosin heavy chain (β-MyHC), encoded by MYH7 . In several HCM patients, unequal fractions of mutant mRNA and protein have been detected and higher fractions of mutant protein have been associated with a more severe disease course [1, 2]. However, it is unknown which mechanisms cause the unequal allelic ratios in the HCM patients with missense mutations