Question

For a trait such as human blood types that have multiple alleles (there are 3: A, B, and 0), how many alleles can be present in the somatic cells of an individual?

• A. One
• B. Two
• C. Three
• D. Four
• E. Eight

Answer 1

Answer: (B)

Two

Human ABO blood grouping is an example of multiple alleles. A set of three multiple alleles on the chromosome 9 is responsible for the four blood types. The genes controlling blood types has been labelled as I (standing for isohaemogglutinin). The six genotypes that give rise to four phenotypes represent various combinations of three ABO alleles i.e. I^A , I^B and i.

Hence, the number of alleles that can be present in the somatic cells of an individual are two.

So, the correct answer is 'two'.