Question

What are multiple alleles? Describe multiple alleles with the help of ABO blood groups in man.

Answer 1

Multiple allelism refers to the presence of more than two contrasting alleles for a gene. Human blood group inheritance is the governed by three alleles namely I${}^A$, I${}^B$ and i. Alleles I${}^A$ and I${}^B$ show codominance as I${}^A$ I${}^B$ genotype produce AB blood group that exhibits characters of both I${}^A$ and I${}^B$ alleles. Allele 'i' is recessive to both I${}^A$ and I${}^B$; I${}^A$ i and I${}^B$ i phenotypes exhibit A and B blood groups respectively.