Question

In 30% of cases, mutations in MYH7 gene give rise to the Hypertrophic cardiomyopathy phenotype. HCM is classified as a dominant trait. This means that:

a) Both alleles must be mutated for HCM to occur
b) Only one mutated allele is needed for HCM
c) HCM is caused by environmental factors
d) HCM is a recessive trait

Answer 1

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder, meaning only one mutated allele of the MYH7 gene is needed for the phenotype to manifest.The correct answer is option b.

Step-by-step explanation:

In 30% of cases, mutations in the MYH7 gene give rise to the phenotype of Hypertrophic cardiomyopathy (HCM), which is classified as a dominant trait. Therefore, the correct answer to the student's question is that only one mutated allele is needed for HCM to occur, making option b) the correct one. An autosomal dominant disorder is expressed when just one gene is affected.



In the case of HCM, a person with one mutated MYH7 allele will show the disease phenotype. Other genetic diseases that follow an autosomal dominant inheritance pattern include achondroplastic dwarfism, Marfan syndrome, and Huntington's disease. This pattern contrasts with autosomal recessive inheritance, where two copies of the mutated gene are necessary to express the phenotype.