What is the inheritance pattern of hypertrophic cardiomyopathy (HCM)?

Hypertrophic cardiomyopathy (HCM) primarily follows an autosomal dominant inheritance pattern. This means that only one copy of the mutated gene, inherited from either parent, is sufficient to cause the disease. HCM is most commonly associated with mutations in genes that encode proteins of the myocardial sarcomere, and these mutations can be passed on to offspring with a 50% chance for each child.

The dominant nature of its inheritance pattern explains why HCM can appear in individuals who do not have a family history of the condition; it may have arisen from a new mutation in the gene. Understanding the autosomal dominant pattern is crucial for risk assessment and genetic counseling for affected families, as it allows for the identification of at-risk individuals even in the absence of overt symptoms.

Other inheritance patterns such as X-linked recessive, autosomal recessive, or mitochondrial inheritance are not applicable to HCM, as they typically manifest in different disease contexts and have different implications for transmission and expression in families. This solidifies the concept that the autosomal dominant inheritance of HCM is not only the most common but also the most clinically relevant pattern.