Mendelian Genetics

Question

Mistakes were made in the maternity ward and two sets of parents claim to be the real parents of one child. Determine the biological parents in each of the following cases.

 

a. Situation 1: the child has Type AB blood, Mother #1 has Type B blood, Father #1 has Type B blood, Mother #2 has Type B blood and Father #2 has Type A blood. 

 

b. Situation 2: the child has Type O blood, Mother #1 has Type B blood, Father #1 has Type A blood, Mother #2 has Type B blood and Father #2 has Type AB blood. 

Answer 1

In situation a. the parents would have to be #2 while in b. the parents would have to be the #1 pair. 

 

Situation a. #1 parents are both type B and cannot provide the A antigen while #2 parents one is B and the other is A and a combination of the two coudl result in AB blood group

 

Situation b. Father 2 has AB antigen while mother 2 is B so the child could be A, B or AB but not O. With parents #1 father is A and mother is B with the possibility of the child having an O type blood