Question

Total fingerprint ridge count exemplifies a polygenic inheritance pattern. Penrose (1969) and others have suggested that a minimum of seven gene loci contribute to TRC, but a fourlocus model is hypothesized in the problems that follow. Thus, AABBCCDD represents the genotype for maximum ridge count and aabbccdd symbolizes the genotype for the minimum ridge count. Assume that each active (dominant) allele adds 12 ridges to the TRC of the male and 9 to the TRC of the female and that having the genotype aabbccdd produces a baseline TRC of 80 for males and 70 for females.

If an AaBBCcdd male mates with an AABbCcDd female,

a. What is the minimum number of active alleles possible in a child this couple could produce?

b. What would be the probability of producing a child with the minimum number of active alleles?

c. What would be the TRC for this child if it were male?

d. What would be the TRC for this child if it were female?

Please help me with all the questions and show your working out/reasoning so i can understand. Thank you

Answer 1

Ans)

A) minimum no of active allele in child (AaBbccdd) produced by cross between AaBBCcdd male and AABbCcDd is 2.

B) probability of producing a child with the minimum no of active allele is1/32

C) TRC of Child(AaBbccdd) if it is male=baseline for male +(no. Of dominant active allelex contribution by each dominant allele in male)=80+(2x12)=104

D) TRC of this child if it is female=baseline for female+(total no ofdominant active allele x contribution by each dominant allele in female)=70+(9x2)=88