Concept explainers
To analyze:
The presence of cheek and chin dimples is dominant to the lack of dimples, and the ability to taste the compound PTC is dominant to the failure to taste the compound, in humans. Both these qualities are autosomal and unlinked. The allele frequencies for dimples are
Calculate the frequency of genotypes for each gene and the frequency of each
Estimate the expected frequencies of the four probable phenotype combination: Dimpled nontasters, dimpled tasters, undimpled tasters, and undimpled nontasters.
Introduction:
Hardy-Weinberg explains that allelic frequency in a population can be maintained but population should fulfill some criteria i.e. there should be random mating, no mutation, large
Hardy-Weinberg mathematical equation to calculate the allelic and genotypic frequency is
Want to see the full answer?
Check out a sample textbook solutionChapter 20 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
- . Full color (D) is dominant over dilute color (d). Of 325 cats observed, 194 have full color and 131 have dilute color. a. If the cats are in Hardy-Weinberg equilibrium, what is the frequency of the dilute allele? b. How many of the 194 cats with full color are likely heterozygous?arrow_forwardWhat kind of test would best determine whether genotypic frequencies match the Hardy-Weinberg model? Group of answer choices Chi-square with three rows (homozygous dominant, heterozygous, homozygous recessive) Chi-square with two rows (dominant and recessive alleles) T-test between homozygous and heterozygous T-test between dominant and recessive allelesarrow_forwardAn autosomal locus has alleles A and a. We are given the frequency of individuals with the autosomal recessive phenotype. Which of the following statements is TRUE? Choose all that are true. Note: HWE = Hardy-Weinberg equilibrium a) If we assume HWE, we can calculate both allele frequencies b) If we assume HWE, we can calculate the genotype frequencies that we weren't given c) We can calculate both allele frequencies even if we don't assume HWE d) We can calculate q = Freq(a) even if we don't assume HWE e) Even if we don't assume HWE, we can calculate the genotype frequencies that we weren't givenarrow_forward
- In domestic chicken, feather colour and shape are two traits which are controlled by autosomal alleles that are co-dominant. Table 2 shows the alleles and phenotype of both traits. The heterozygous state for feather colour is grey while the heterozygous state for feather shape is mildly frizzled. TABLE 2 Trait Allele Effect Feather colour CB Produces black feathers in homozygotes CW Produces white feathers in homozygotes Feather shape SS Produces straight feathers in homozygotes SF Produces frizzled feathers in homozygotes (a)A farmer bred a black frizzled rooster with a grey mildly frizzled hen. Draw a genetic diagram to show the expected results of this cross. Include in your answer the phenotypic ratios. (b)Is it necessary to do a test cross to determine the genotypes of the offspring? Explain your answer. (c)The farmer would like all his chickens grey and mildly…arrow_forwardThe following table shows the number of dogs for certain tail lengths in a population of dogs. Tail Length Number of Dogs very short (less than 1 inch) 2 short (1–5 inches) 5 medium (5–10 inches) 15 long (10–15 inches) 5 very long (15–25 inches) 2 Based on this data, what type of trait is tail length in dogs? (a) Mendelian (b) codominant (c) (d) polygenicarrow_forwardAssuming there are only two alleles at a given locus, if the frequency of one allele is 0.3, what is the frequency of the other allele?arrow_forward
- The ability to taste the compound PTC is controlled by a dominant allele T, while individuals homozygous for the recessive allele (t) cannot taste PTC. In a population consisting of 500 individuals, 347 are tasters and 153 are non-PTC tasters. Calculate the frequency of the T and t alleles in this population, and frequency of the genotypes.arrow_forwardThe ability to taste the compound PTC is controlled by a dominant allele T, while individuals homozygous for the recessive allele (t) cannot taste PTC. In a population consisting of 500 individuals, 347 are tasters and 153 are non-PTC tasters. Calculate the frequency of the T and t alleles in this population, and frequency of the genotypes. (Please train yourself to use the Hardy-Weinberg equation.) To present your answers, follow the format in the picture below.arrow_forwardIn a lab population of mice, a locus affecting fur color has 2 alleles. The B allele produces brown fur, while the b allele produces white fur. Heterozygote individuals (Bb) have beige fur. In a sample of 150 mice, 48 mice have white fur, and 13 have beige fur. What is the frequency of the B allele? Answer with two decimals precision (0.00).arrow_forward
- Using the HardyWeinberg Law in Human Genetics Suppose you are monitoring the allelic and genotypic frequencies of the MN blood group locus (see Question 2 for a description of the MN blood group) in a small human population. You find that for 1-year-old children, the genotypic frequencies are MM = 0.25, MN = 0.5, and NN = 0.25, whereas the genotypic frequencies for adults are MM = 0.3, MN = 0.4, and NN = 0.3. a. Compute the M and N allele frequencies for 1-year-olds and adults. b. Are the allele frequencies in equilibrium in this population? c. Are the genotypic frequencies in equilibrium?arrow_forwardUsing the HardyWeinberg Law in Human Genetics In a given population, the frequencies of the four phenotypic classes of the ABO blood groups are found to be A = 0.33, B = 0.33, AB = 0.18, and i = 0.16. What is the frequency of the i allele?arrow_forwardAssume that human ear length is influenced by multiple genetic and environmental factors. Suppose you measure ear length in three groups of people, in which group A consists of five unrelated people, group B consists of five siblings, and group C consists of five first cousins. a. With the assumption that the environments of all three groups are similar, which group should have the highest phenotypic variance? Explain why. b. Is it realistic to assume that the environmental variance for each group is similar? Explain your answer.arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning