Welcome to Connect. I’d like to share a few resources that might help shed some more light on your concerns.
MYBPC3 mutations are amongst the most frequent causes of hypertrophic cardiomyopathy. In some studies, MYBPC3 mutants have been associated with a less severe form of HCM with late clinical onset, while other studies have described MYBPC3 mutations to be associated with more severe disease onset, increased LV hypertrophy, and increased frequency of heart failure and sudden cardiac death. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0187948