A, Lifetime risk of HCM, defined as the percent chance of a diagnosis of hypertrophic cardiomyopathy by age 80 years (n = 129 incident cases), in strata of rare variant carrier status and polygenic risk. B, Cumulative incidence plots for HCM in strata of rare variant carrier status and polygenic risk. Rare variant carrier status was defined as the presence of an HCM–American College of Medical Genetics and Genomics (ACMG) variant. Low polygenic risk was defined as the lowest quintile, intermediate risk as quintiles 2 through 4, and high risk as the top quintile of the polygenic risk score (PRS) distribution. Error bars denote 95% CI. Data analysis was conducted in the UK Biobank.