The example of a gene having multiple alleles is ABO blood system in human.
Explanation:
Sometimes the gene can have three or more alleles on the same locus, but in reality only 2 alleles are present in the individual.
It is a deviation from Mendel's law of inheritance.
There are three allelic forms of gene of blood group on the locus as A,B and O and have more than two phenotype for a gene.
Type A (iA), Type B (IB), OR type O
the 3 combinations can give genotype of
type A, Type B, type AB or O BLOOD GROUPS.
Type A can be homozygous as IA IA or heterozygous as ( having one O allele) IAI
same genotype for B is also there.
Type O is recessive with two O alleles.
Since A or B type are equally dominnat they give rise to AB type.
