Question

Because blood type is inherited, it is used as evidence in paternity cases. A mother is blood type A (that is her phenotype). Her child is type O. Three men claim paternity. Use what you have learned about blood type and Punnett squares to solve the problem.

Baby’s genotype _________

What does the mother’s genotype have to be? Why?

What allele did the baby get from its mother?

What allele did they get from their father? _________

Use Punnett squares to show whether the following men are possible fathers. Use the same mother in all three Punnett squares. Identify the most likely father.

Male 1: type AB Male 2: type A Male 3: type O

Answer 1

The baby’s GENOTYPE would be OO or Xo Xo as O blood type is a recessive trait and needs 2 O’s to appear. The mother would have to be Xa Xo or AO. Which would mean that the Baby received the O from the mother meaning that they would have to receive another O from the father.

Male 1: cannot be the father because he cannot pass a O allele

Male 2: can be the father if his genotype is AO as the mothers is

Male 3: is most likely the father as his genotype is OO meaning he has more of a chance to give off that allele