Homework problem set 3

14a) Which of the following genotype frequencies are in Hardy-Weinberg equilibrium? Estimate selection for or against each genotype. Based on deviation from Hardy-Weinberg equilibrium, what form of selection might be responsible for each that is not in Hardy-Weinberg equilibrium? genotypes A1A1 A1A2 A2A2

genotype frequencies 49% 15% 36% Allele freq p = 0.565 q = 0.435 p2, 2pq, q2 31.9% 49.2% 18.9% difference +17.1% -32.2% +17.1% selection 1 1-s 1 HW equilibrium? NO, disruptive or varying selection

14b) Genotypes A1A1 A1A2 A2A2 Genotype freq 49% 26% 25% Allele freq p = 0.38 q = 0.62 p2, 2pq, q2 38.4% 47.2% 14.4% difference +10.6 -21.2 +10.6 selection 1 1-s 1 HW equilibrium? NO, disruptive selection

14c) Genotypes A1A1 A1A2 A2A2 Genotype freq 49% 35% 16% Allele freq p = 0.665 q = 0.335 p2, 2pq, q2 44.2% 44.6% 11.2% difference +4.8 -9.6 +4.8 selection 1 1-s 1 HW equilibrium? NO, disruptive selection

14d) Genotypes A1A1 A1A2 A2A2 Genotype freq 49% 42% 9% Allele freq p = 0.7 q = 0.3 p2, 2pq, q2 49% 42% 9% difference 0 0 0 HW equilibrium? YES e) 49% 47% 4% NO directional with dominance (1, 1, 1-s)

14e) Genotypes A1A1 A1A2 A2A2 Genotype freq 49% 47% 4% Allele freq p = 0.725 q = 0.275 p2, 2pq, q2 52.6% 39.9% 7.6% difference -3.6 +7.1 -3.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

15a) Genotypes A1A1 A1A2 A2A2 Genotype freq 36% 28% 36% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference +11 -22 +11 selection 1 1-s 1 HW equilibrium? NO, disruptive selection

15b) Genotypes A1A1 A1A2 A2A2 Genotype freq 25% 50% 25% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference 0 0 0 HW equilibrium? YES

15c) Genotypes A1A1 A1A2 A2A2 Genotype freq 16% 68% 16% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference -9 +18 -9 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

15d) Genotypes A1A1 A1A2 A2A2 Genotype freq 9% 82% 9% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference -16 +32 -16 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

15e) Genotypes A1A1 A1A2 A2A2 Genotype freq 4% 92% 4% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference -21 +42 -21 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

16a) Genotypes A1A1 A1A2 A2A2 Genotype freq 4% 60% 36% Allele freq p = 0.34 q = 0.66 p2, 2pq, q2 11.6% 44.9% 43.6% difference -7.6 +15.1 -7.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

16b) Genotypes A1A1 A1A2 A2A2 Genotype freq 9% 66% 25% Allele freq p = 0.42 q = 0.58 p2, 2pq, q2 17.6% 48.7% 33.6% difference -8.6 +17.3 -8.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

16c) Genotypes A1A1 A1A2 A2A2 Genotype freq 16% 68% 16% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference -9 +18 -9 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

16d) Genotypes A1A1 A1A2 A2A2 Genotype freq 25% 66% 9% Allele freq p = 0.58 q = 0.42 p2, 2pq, q2 33.6% 48.7% 17.6% difference -8.6 +17.3 -8.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection

16e) Genotypes A1A1 A1A2 A2A2 Genotype freq 36% 60% 4% Allele freq p = 0.66 q = 0.34 p2, 2pq, q2 43.6% 44.9% 11.6% difference -7.6 +15.1 -7.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection, possibly heterozygote advantage or antagonistic selection

17a) Genotypes A1A1 A1A2 A2A2 Genotype freq 100% 0% 0% Allele freq p = 1.0 q = 0.0 p2, 2pq, q2 100% 0% 0% difference 0 0 0 HW equilibrium? YES, but fixation but could be due to drift or selection

17b) Genotypes A1A1 A1A2 A2A2 Genotype freq 82% 17% 1% Allele freq p = 0.905 q = 0.095 p2, 2pq, q2 81.9% 17.2% 0.9% difference +0.1 -0.2 +0.1 (negligible) HW equilibrium? YES

17c) Genotypes A1A1 A1A2 A2A2 Genotype freq 25% 50% 25% Allele freq p = 0.5 q = 0.5 p2, 2pq, q2 25% 50% 25% difference 0 0 0 HW equilibrium? YES

17d) Genotypes A1A1 A1A2 A2A2 Genotype freq 15% 75% 10% Allele freq p = 0.525 q = 0.475 p2, 2pq, q2 27.6% 49.9% 22.6% difference -12.6 +25.1 -12.6 selection 1-s 1 1-s HW equilibrium? NO, stabilizing selection, possibly heterozygote advantage or antagonistic selection

17e) Genotypes A1A1 A1A2 A2A2 Genotype freq 82% 0% 18% Allele freq p = 0.82 q = 0.18 p2, 2pq, q2 67.2% 29.5% 3.2% difference +14.8 -29.5 +14.8 HW equilibrium? NO, most consistent with demic metapopulation or inbreeding