Peter D. Fields Academia, Research, and whatnot

Caballero QG Chp. 2, Problem set Q3 and Q4 (R)

Problem 3 A large population of Drosophila melanogaster has been subdivided into 64 lines of constant census size N = 40 that are maintained with panmixia for 50 generations. A biallelic genetic marker is found in generation t = 0 with allele frequency q0 = 0.4 for the minority allele. Calculate for generation t = 50: (a) the expected frequency... Read more

Caballero QG Chp. 2, Problem set Q2 (R)

In an analysis of a sample of 200 individuals, haplotypes were found for two SNPs with alleles A and a, and B and b, respectively, as shown in the following table:             Haplotype AB Ab aB ab Total Number 29 37 ... Read more

Caballero QG Chp. 1, Problem set Q2 (R)

Chapter 1: Continuous variation Problem 2 The following table shows the number of sternopleural bristles in 50 individuals of Drosophila melanogaster. 24 24 21 21 21 20 19 19 18 24 23 25 22 24 22 22 18 20 22 ... Read more

Caballero QG Chp. 1, Problem set Q1 (R)

Chapter 1: Continuous variation Problem 1 In the cross between two pure lines, a heterozygous hybrid was obtained for 20 biallelic loci that affect a quantitative trait. For these loci, one allele has no effect on the trait and the other increases it by one unit. (a) How many genotypic classes would be found in the offspring by self-fertilizati... Read more

Caballero QG Chp. 2, Problem set Q1.b (R)

(b) Is the population in Hardy-Weinberg equilibrium for that locus? In order to test if the population is in Hardy-Weinberg equilibrium (HWE) we need to determine the observed vs. expected distribution of the different genotypes given the observed allele frequencies. Above we estimated the frequences of A1,A2,A3. Let’s recall our allele frequen... Read more