The Concept of Multiple Allelism
Multiple allelism describes genes that exist in three or more allelic forms. Although diploid organisms, like humans, normally possess only two alleles of each gene, there are multiple alleles of many (if not most) human genes present in a population. Blood type is one example of multiple allelism. There are three alleles for blood type (HBB gene) in humans: IA, IB, and i.
Incomplete Dominance
Sickle cell anemia, which is caused by a mutation in the gene...