What genetic force leads to the variability in the percentage of mutant mtDNA molecules that are present in the children of a mother who exhibits heteroplasmy for the mutation?
A) Positive selection
B) Negative selection
C) Genetic bottleneck
D) Reduced fitness
E) Balancing selection

Question

Quizplus · Accepted Answer

Genetic bottleneck refers to the sharp reduction in the size of a population due to environmental events or other changes, leading to a limited number of individuals passing on their genetic material to the next generation. In the context of mitochondrial DNA (mtDNA), during the process of oogenesis (egg formation), a reduction in the number of mitochondria occurs, which can lead to a significant variation in the proportion of mutant versus normal mtDNA molecules passed on to the offspring. This phenomenon explains the variability in the percentage of mutant mtDNA molecules in children of a mother with heteroplasmy, as only a subset of the mother's mtDNA is transmitted, potentially altering the ratio of mutant to wild-type mtDNA in the next generation.

What Genetic Force Leads to the Variability in the Percentage