A pedigree was examined over four generations of a family with an abnormal rate of genetic disease. Scientists observed that males and females alike were affected by the disease but only when their mother was also affected. The children of affected males were all normal. All the children of affected females were affected. Which of the following describes this inheritance pattern?

Question

Quizplus · Accepted Answer

This pattern is characteristic of mitochondrial inheritance, where the mitochondria (and thus mitochondrial DNA) are passed from mother to all her children, but not from father to child. This explains why all children of affected females are affected, while children of affected males are not.

A Pedigree Was Examined Over Four Generations of a Family