Question

if a person who is blood type O marries a person who is blood type A, what are the possible blood types their children could have

Answer 1

Answer:

The possible blood types their children could have are A or 0.

Explanation:

  The I gene determines the blood type of a person. I is the dominant allele, while i is the recessive allele.

• IA dominant over i. The person presents A type of antigens.

• IB dominant over i. The person presents B type of antigens.

• IA and IB are codominant. The person presents both types of antigens, A and B.
• i is the recessive allele. The person does not present any antigen.

Cross: a person who is blood type O with a person who is blood type A

Parental)    ii      x     IA-

Gametes) i   i          IA   -

Punnet Square)   IA            -

                     i      IAi           -i

                     i      IAi           -i

The - symbol represents the possibility of either IA allele or i allele. This is, the parental with blood type A might have the genotype IAIA or IAi

F1)  2/4 = 1/2 IAi

     2/4 = 1/2    -i  (-i could be either IAi or ii, depending on the genotype of the parental with blood type A)

• Option 1: ii  x  IAIA

F1)  100% IAi (The whole progeny will have blood type A)

• Option 2: ii  x  IAi

F1) 50% IAi (Half of the progeny will have blood type A)

    50% ii (Halfa of the progeny will have blood type 0)  

The possible blood types their children could have are A or 0.