Genetics Answers

1. [25%] Consider selection in a predator-prey model. Assume two haploid organisms. In the predator organism we consider a locus with alleles A and a; in the prey organism, we consider a locus with alleles B and b. Assume allele A provides the predator an advantage to hunt prey with genotype B. Plentiful prey of genotype B give A-predators a selective advantage. Then wA = 1 + fB s − t, where s and t are selection coefficients.
(A) [10%] Calculate the change in allele frequencies in the predator per generation. Simplify your equations.
(B) [10%] Assume now that allele B in the prey is disadvantaged if allele A is common in thepredator. ThuswB =1−fAs + t,wheres and tareselectioncoefficients. Calculatethe change in the allele frequencies in the prey in one generation. Simplify your equations.
(C) [5%] Is there a non-trivial equilibrium for fA and fB such that ∆fA = 0 and ∆fB = 0? By non-trivial, we mean when neither A nor B has frequency 0 or 1. If a non-trivial equilibrium exists, then characterize it?

Individuals with Duchenne muscular dystrophy are usually confined to a wheelchair by age 12 and often die of respiratory infection or cardiac failure shortly thereafter. Based on this information, would you expect any women to have Duchenne muscular dystrophy? ____________________________ Why or why not?

_ A woman with normal vision but whose father was red-green colorblind has a child with a male with normal vision. What is the probability they will produce a colorblind daughter?
What is the probability of a colorblind son? __________
Of all sons, what is the probability that one of them will be colour-blind?

With the help of clear and labelled diagrams describe how aneuploids are formed.