A polygenic trait is controlled by three pairs of alleles. What are the two extreme genotypes for this trait?
Step 11 of 2
Polygenic inheritance can be compared to a bell-shaped curve, wherein the people at the two ends of the curve have the extreme genotypes of a trait (dominant and recessive) while the people in the middle have a combination of both the dominant and recessive alleles.
Let’s say we have an individual who has a genotype of AABBCC, which is dominant for all the alleles for a tall height. This person is at the end of the curve. On the other hand, a person with a short height, which has a genotype of aabbcc (recessive for all the alleles), is at the other end of the curve. People with average height would be at the middle of the curve. These people can have genotypes AaBbCC, AaBBcc, or any other combination of the dominant and recessive alleles.