In this chapter, we focused on a mode of inheritance referred to as quantitative genetics, as well as many of the statistical parameters utilized to study quantitative traits. Along the way, we found opportunities to consider the methods and reasoning by which geneticists acquired much of their understanding of quantitative genetics. From the explanations given in the chapter, what answers would you propose to the following fundamental questions:

How do we know that monozygotic twins are not identical genotypically as adults?

Video transcript

Hi everybody. Let's take a look at this practice problem. Together in mono psychotic twins, what could have contributed to their phenotype pick variants recall that mona's psychotic twins are genetically identical. They come from one zygote and phenotype pick variants is the variety of phenotype that is observed. Now recall that phenotype is influenced by two things and we can infer therefore that phenotype IQ invariants. Excuse me, phenotype IQ variants would be influenced by two things and that is genetics and the environment. Having reviewed this, let's look at our options is the correct answer. A gina typical variants, be behavioral variants, see environmental variance and D. Irritable variance. So we can eliminate both B. And D. We know that Vienna typical variants should be influenced by either genetics or environment. Now for a gene, a typical variance that would be referring to the genetics. Well, mono psychotic twins have the same D. N. A. Therefore you would expect to see the same phenotype and that's not going to contribute to the phenotype IQ variants. So A. Is also wrong. The correct answer therefore, is c environmental variants. Different environmental factors can contribute to the phenotype. Pick variants. Alright, everybody, I hope you found this helpful. And I'll see you soon for the next practice problem