The ABO blood group system consists of four different blood groups, which describe whether an individual's red blood cells carry the A antigen, B antigen, both, or neither. The ABO gene has three alleles: I A, I B , and i. The i allele is recessive to both I A and I B , while the I A and I B alleles are codominant. Individuals homozygous for the i allele are Type O, with neither A nor B antigens.

A study was conducted to investigate allele frequencies for the ABO alleles in a population in Lagos, Nigeria.2 Use the reported allele frequencies to answer the following questions. Alleles inherited Blood type Frequency IA and IA A 0.02 IA and [3 AB 0.04 IA and 1' A 020 IE and 1'3 B 0.02 I3 and i B 0.20 1' and f O 0.52 (1) Suppose that two parents are known to have Type A blood. What is the probability that their rst child has Type 0 blood? e) Given that two parents are known to have Type A blood and their first child also has Type A blood, what is the probability that their second child has Type 0 blood? f) In language accessible to someone who has not taken a statistics course, briey explain the reasoning behind why the probabilities in parts (1) and e) differ