Question

Some human diseases are caused by mutations in mitochondrial genes. Which of the following statements is FALSE?

A. Mutations associated with mitochondrial diseases often affect cells with a high demand for ATP.

B. Human mitochondrial diseases follow a maternal inheritance pattern.

C. Heteroplasmy plays a key role in the severity of disease symptoms.

D. Human mitochondrial diseases follow Mendelian inheritance patterns.

Answer 1

The statement pertaining to option D is false. Human mitochondrial diseases do not follow Mendelian inheritance patterns. These diseases are due to defects caused in the mitochondrial genome and they tend to not follow the mainstream genetic laws i.e Mendelian laws of heredity. They can also arise from nuclear gene disorders. Mutations in the nuclear gene can also result in abnormalities of the mitochondrial genome. They follow maternal inheritance pattern. They can also occur due to single mitochondrial deletions i.e as a result of point mutation.