Geneticist Geri notices that a woman exhibits Trait L. With certainty, she asks the woman, "Which of your parents also exhibits this trait?" The woman is surprised that Geri knew that one of her parents had to also display Trait L. Knowing which fact would have cleared up the woman's confusion?

Question

Quizplus · Accepted Answer

If Trait L is governed by a dominant allele, then the woman only needs to inherit one copy of the allele from either parent in order to exhibit the trait. This would explain why Geri knew that one of her parents must also display Trait L. If Trait L is governed by a recessive allele, then both of the woman's parents would need to carry at least one copy of the allele in order for her to exhibit the trait. If Trait L involves polygenic inheritance, then it could be that multiple genes contribute to expressing the trait and it may not necessarily require one parent to display the trait in order for the woman to exhibit it.

Geneticist Geri Notices That a Woman Exhibits Trait L