A, B, and O blood type in humans is controlled by a single gene with three alleles: I^A, I^B and i. Imagine a fourth allele for blood type, I^C. If it is codominant with I^A and I^B, and dominant to i, how many possible blood type phenotypes are there?

Question

Quizplus · Accepted Answer

With the addition of a fourth allele (I^C) that is codominant with I^A and I^B, and dominant over i, the possible phenotypes would be: A, B, C, AB, AC, BC, and O, making a total of seven possible phenotypes.

A, B, and O Blood Type in Humans Is Controlled