This is a note for the book Population Genetics: A Concise Guide (Second Edition). Page 31 Problem 2.9 Graph -ΔNH and ΔuH as function of H for N = 104 and u = 5×10-5. Do the lines intersect where you expect them to? Note: Output: In this situation, 4Nu = 4×104×10-5 = 2, when H > […]
This is a note for the book Population Genetics: A Concise Guide (Second Edition). Page 30 Problem 2.8 Graph Equation 2.7 as a function of 4Nu. What value of 4Nu gives a reasonable fit to the average heterozygosity for proteins as described by electrophoretic studies in humans? Note: Equation 2.7: Set t = 4Nu Output: Proteins
This is a note for the book Population Genetics: A Concise Guide (Second Edition). Page 28 Problem 2.5 Graph simultaneously both Formula 2.4 and Formula 2.5 as a function of N for N from 1 to 100. Is the approximation to your liking? Formula 2.4 Formula 2.5 Code: Output: So we can trust that Formula 2.5
This is a note for the book Population Genetics: A Concise Guide (Second Edition). Page 27 Problem 2.4 Graph Ht and Gt for 100 generations with H0 = 1 and population sizes of 1, 10, 100, and 1,000,000. Note: According to the formula: Output: This indicates that genetic drift has a greater impact on small populations
Page 16 Problem 1.7 Derive the Hardy-Weinberg law for a sex-linked locus. Let the initial frequency of A1 in the females be pf and in the males, pm. Follow the two alleles frequencies in successive generations until you understand the allele-frequency dynamics. Then, jump ahead and find the equilibrium genotype frequencies in females and males.
Page 16 Problem 1.6 Perform a Chi-squared test for agreement of the data in Table 1.2 with the predictions of the Hardy-Weinberg law. Note: Table 1.2 see #note Population Genetics A Concise Guide (4) Run Chi-squared test in Python: Output:
Page 15 Problem 1.5 Graph the ratio of the frequencies of A1A2 heterozygotes to A2A2 homozygotes as a function of q using both the exact and the approximate formulae. Note: Exact formula by using Python: Output: Approximate formula by using Python: Output:
Page 15 Problem 1.4 Graph the frequencies of homozygotes and heterozygotes as a function of the allele frequency, p. At what allele frequency is the frequency of heterozygotes maximized? Note: According to the Hardy-Weinberg law, p2+2pg+q2=1, where 2pq is the frequency of heterozygotes. q=1-p, so to maximize 2pq is to maximize 2p(1-p), so p=0.5. When
Page 5 The number of polymorphic sites within melanogaster and fixed differences between melanogaster and erecta are summarized in the folloing table: Polymorphic Fixed Silent 13 26 39 Replacement 1 10 11 14 36 50 Note: 2 X 2 Contingency Chi-square calculation: P > 0.05 (degrees of freedom dof = 1), thus that the two