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a. | What is the confidence interval for p = 0.5 when N = 100,000? |
b. | What is the confidence interval for p = 0.5 when N = 10? |
c. | How are the results in parts (a) and (b) related to the consequences of a population bottleneck? |
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Genetics: From Genes to Genomes
- How Can We Measure Allele Frequencies in Populations? The MN blood group is a single-gene, two-allele system in which each allele is codominant. Why are such codominant alleles ideal for studies of allele frequencies in a population?arrow_forwardSmall population size causes genetic drift because ofchance sampling of different alleles from one generation to the next. We can predict how much geneticdrift occurs for a given population size using binomialsampling statistics. With a population of size N, wecan estimate that 95% of the time the allele frequency(p) in the next generation will be withinthe confidence interval of p ± 1.96 (√p(1 − p)2N ),where p(1 − p)2Nis an estimate of the statistical variancein allele frequencies from one generation to the nextwith random sampling of 2N alleles each generation. a. What is the confidence interval for p = 0.5 whenN = 100,000?b. What is the confidence interval for p = 0.5 whenN = 10?c. How are the results in parts (a) and (b) related tothe consequences of a population bottleneck?arrow_forwardIn a donor population, the allele frequencies for the normal (HbA) and sickle-cell alleles (HbS) are 0.9 and 0.1 respectively. A group of 550 individuals migrates to a new population containing 10,000 individuals; in the recipient population, the allele frequencies are HbA = 0.99 and HbS =0.01. What will be the genotype frequencies of the conglomerate population in the next generation, assuming it achieves Hardy-Weinberg equilibrium in one generation?arrow_forward
- A sample of 100 individuals from a population that is dimorphic at the A locus has genotype counts as follows. AA: 30 Aa: 60 aa: 10 a) What are the allele frequencies in the population? b) What are the expected genotype frequencies, if the population were at HardyWeinberg equilibrium? c) Is the proportion of heterozygotes lower or higher than expected at Hardy-Weinberg equilibrium? What deviations from the assumptions of the model would best explain the observed difference?arrow_forwardIf gene A/a is not in Hardy-Weinberg equilibrium due to natural selection such that individuals with the genotype AA have a fitness value of 1.0, heterozygotes have only slightly reduced fitness at 0.9, and individuals with the genotype aa have a fitness value of 0.6, what kind of change in allele frequency would you expect to see over time assuming you start with equal frequencies of the 2 alleles?arrow_forwardFor two 2 alleles at a locus, which of the following sets of genotype frequencies would you expect came from a very small population that is experiencing significant genetic drift? a) AA = 0.01, Aa = 0.18, aa = 0.81 b) BB = 0.04, Bb = 0.32, bb = 0.64 c) CC = 0.36, Cc = 0.48, cc = 0.16 d) DD = 0.125, Dd = 0.425, dd =0.45 e) EE = 0.0625, Ee = 0.375, ee = 0.5625arrow_forward
- Nieman-Pick Syndrome involves a defective enzyme, sphyngomylinase. It is usually fatal before the age of 3. The defective allele frequency is 0.01 in Ashkenazi populations. Let’s call the healthy allele A, and the lethal allele a. a) What is the frequency of allele A? Assuming Hardy-Weinberg equilibrium, how many people do you expect to have the three genotypes in a population of 10,000? b) AA:_______ c) Aa:________ d) aa:_________arrow_forwardAssume that the frequency of gene B in a hypothetical population Is 0.63, that there are only two alleles (B and b) of the gee in the population, that allele B is dominant over allele b, that neither allele has a selective advantage over the other, and that the population is at equilibrium with regard to this particular gene. What proportion of the population is expected to have the phenotype specified by the B allele according to the Hardy-Weinberg formula? 0.47 0.87 0.67 0.40 0.37arrow_forwardWhich of the following populations is not in Hardy-Weinberg equilibrium? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a. A population with 23 homozygous recessive individuals (yy), 7 homozygous dominant individuals (YY), and 4 heterozygous individuals (Yy) b. A population that receives new individuals from a normally distant population. c. q + p = 1 d. A population in which the allele frequencies do not change over timearrow_forward
- If a population is in Hardy-Weinberg Equilibrium, where the dominant allele frequency is 0.2. Which of the following is true about the recessive allele frequency? Select the formula that you would use to find it. q = 1- 2pq q = p/2 q=1-p q = 0.05 then tell us if the statement "Populations in nature are ALWAYS in Hardy-Weinberg Equilibrium" is TRUE or FALSEarrow_forwardAssume that the frequency of gene B in a hypothetical population Is 0.63, that there are only two alleles (B and b) of the gee in the population, that allele B is dominant over allele b, that neither allele has a selective advantage over the other, and that the population is at equilibrium with regard to this particular gene. And how many individuals in this population are expected to be of genotype BB according to the Hardy-Weinberg formula? (Assume that the total population size is 150) 71 52 118 60 131arrow_forwardA given autosomal locus has three possible alleles (A1, A2, and A3). Assuming that the numbers of individuals with the six possible genotypes are as follows, what would be the frequency of the A1 allele in the population? A1A1 = 30 A1A2 = 27 A2A2 = 12 A1A3 = 17 A2A3 = 10 A3A3 = 4 What would be the frequency of the A1A1 genotype? Assume the population is under Hardy-Weinberg equilibrium. A. 0.182 B. 0.27 C. 0.107 D. 0.317 E. 0.09 F. 0.03arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning