Kent and Emily have a baby boy Dustin by in vitro fertilization. Dustin does not

ID: 322324 • Letter: K

Question

Kent and Emily have a baby boy Dustin by in vitro fertilization. Dustin does not resemble either one of his parents, so they suspect that the clinic made a mistake during the procedure and implanted the wrong embryo. At Dustin's first well-baby checkup they insist that they get his blood type. Baby Dustin is type B-negative. Kent is A-positive and Emily is AB-positive. Given this information answer the following questions. (a) What are Dustin's possible genotypes? __________ (b) What are Kent's possible genotypes? __________ (c) What are Emily's possible genotypes? __________ (d) Is it possible that Dustin is Kent and Emily's son? __________ (e) Explain your answer in (d) __________ Carrie is AB-positive and her father is AB-negative. Carrie marries Ryan, who is AB-negative. (f) What is Carrie's genotype? __________ (g)What is Ryan's genotype? __________ (h) What are the phenotypic ratios of blood types (for both the ABO gene and Rh gene) that would be expected among their children? __________ (Show your work in a Punnett square below!)

Explanation / Answer

Answer:

a). Dustin’s possible genotypes: IA IB : Rh+ Rh+ or IA IB : Rh+ Rh-

b). Kent’s possible genotypes:

IA IA : Rh+ Rh+ or IA IA : Rh+ Rh- or IA i : Rh+ Rh+ or IA i : Rh+ Rh-

c). Emily’s possible genotypes: IB IB : Rh- Rh- or IB i : Rh- Rh-

d). Yes Dustin belongs to Kenta and Emily’s son.

e).

The gamete, IA: Rh+ of Kent’s and the gamete, IB: Rh- of Emily’s fuse to produce IA IB : Rh+ Rh- (AB-positive).

Rh+ is dominant over Rh-

IA & IB are codominant.

f). Carrie’s genotype (AB-positive): IAIB: Rh+Rh-

g). Ryan’s genotype (AB-negative): IAIB: Rh-Rh-

IAIB: Rh+Rh- x IAIB: Rh-Rh-

IARh-

IBRh-

IARh+

IAIA Rh+Rh-

(A+)

IAIBRh+Rh-

(AB+)

IA Rh-

IAIA Rh-Rh-

(A-)

IAIB Rh-Rh-

(AB-)