Question

Dan (blood type O) is being sued by Mary (blood type AB) for paternity of her baby, Beth. Baby Beth is blood type A. Dan doesn't want to pay for DNA testing, because he says that based on blood type, it is impossible for him to be the father. You be the judge: what is true?

a. Dan is not the daddy.

b. Dan could be the father.

c. Dan definitely is the father.

Dan's genotype ___

Mary's genotype ___

Beth's genotype___

Answer 1

b. Dan could be the father.

three alleles at the ABO locus determine the blood group. IA, IB, i.

IAIA, IAi-A type blood

IBIB, IBi-B type blood

ii-O type blood

IAIB- AB-type Blood

Dan (blood type O) is ii, Mary ( blood type AB)-IAIB.

IAIB * ii

	IA	IB
i	IAi ( A type blood )	IBi ( B type blood )
i	IAi ( A type blood )	IBi ( B type blood )

the genotype of Dan- ii

The genotype of Mar- IAIB

Beth`s genotype- IAIA or IAi