ABO blood groups in human beings are controlled by the gene I. The gene I has three alleles - IA,IB and i . Since there are three different alleles, six diffrent genotypes are possible. How many phenotypes can occur?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) –4
The ABO blood group system in humans is governed by a pair of genes, consisting of three types of alleles: IA, IB, and Io.
- Alleles IA and IB are both dominant, while Io is recessive.
- Genotypes IAIA or IAIo result in the A blood group phenotype.
- Genotypes IBIB or IBIo lead to the B blood group phenotype.
- Genotype IAIB leads to the AB blood group phenotype.
- Genotype IoIo results in the O blood group phenotype.
In summary, based on the combinations of these alleles, there are four possible blood group phenotypes: A, B, AB, and O. The gene operates with co-dominance and dominance-recessiveness interactions among its alleles to determine the ABO blood group phenotypes.