It is known that the gene responsible for development of blood groups according to AB0 system has three allele variants. Existence of the IV blood group can be explained by the following variability form:

Answer options

1. Genocopy
2. Mutational
3. Phenocopy
4. Phenotypic
5. Combinative

Explanation

The fourth (IV) group known as the AB blood group includes the combination of both A and B therefore variability form is combinative.