Neurological disorders are rarely caused by dominant genes
A) because all individuals carrying them would be at a major disadvantage in terms of survival and reproduction.
B) unless the dominant genes do not express themselves until after the peak reproductive years.
C) because dominant genes rarely mutate.
D) all of the above
E) both A and B

Question

Quizplus · Accepted Answer

Dominant genes that cause neurological disorders would have a strong negative impact on an individual's survival and reproductive fitness, making it unlikely that they would persist in a population. Therefore, they are rarely caused by dominant genes unless the symptoms do not appear until after peak reproductive years, as in Huntington's disease. Additionally, dominant genes are not immune to mutations, so they can still become a cause of neurological disorders even if they were previously stable. Thus, both option A and B are correct. Choice C is incorrect as dominant genes can still mutate.

Neurological Disorders Are Rarely Caused by Dominant Genes