Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Chapter 22, Problem 21P
In Fig. 22.15:
| a. | Why do some chromosomes in the disease group not carry the disease-causing variant shown in red? |
| b. | Why do some chromosomes in the control group carry the variant shown in red? |
| c. | Discuss how scientists would evaluate data from association mapping studies to find QTLs that contribute to the disease. What would researchers look for? And at the bottom of the figure, why are the nonrandom associations of the disease specifically discussed in terms of the blue alleles? |
| d. | Suppose that researchers identified two different regions of the genome with statistically significant associations of SNPs with the disease in question. In Region 1, SNPs extending over 200 kb of DNA showed such associations. In Region 2, the region containing disease-associated SNPs was 2 Mb long. If you assume that each of these two regions has only one disease-causing variant, which of the two mutations was likely to have occurred earlier in human history? Explain. |
| e. | Given your answer to part (d), explain why the length of the region containing disease-associated SNPs is nonetheless not a perfect indicator of the time in human history at which the disease-causing mutation occurred. |
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Two morphotypes of the newly discovered plant in Mt. Banahaw de Lucban were tested for
linkage of three genes such as the presence of tendril (t+), dense trichomes (d+), and the
presence of secretory cells (sc+). The loci for the mutant genes have been mapped and are
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In a study, an undergraduate student discovered a new enzyme involved in the metabolism of
serotonin. This enzyme is made up of 3 subunits of the same protein. To characterize this
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gene that codes for this protein and performed crosses to measure the effects of genotypes on
enzyme activity.
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A2A2
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A1Α1
B) Explain the reasoning for your prediction.
Enzyme Activity
Chapter 22 Solutions
Genetics: From Genes to Genomes
Ch. 22 - Choose the best matching phrase in the right...Ch. 22 - Suppose you grew genetically identical dandelion...Ch. 22 - How can each of the following be used in...Ch. 22 - Two different groups of scientists studying a rare...Ch. 22 - Which of the following statements would be true of...Ch. 22 - Studies have indicated that for pairs of twins...Ch. 22 - Prob. 7PCh. 22 - Prob. 8PCh. 22 - Table 22.2 lists concordance values for MZ and DZ...Ch. 22 - Prob. 10P
Ch. 22 - Prob. 11PCh. 22 - Two alleles at one locus produce three distinct...Ch. 22 - In a certain plant, leaf size is determined by...Ch. 22 - Compare and contrast the use of SNP genotyping: i...Ch. 22 - Explain the similarities and differences between...Ch. 22 - In Fig. 22.14c, the fw2.2 causal gene was...Ch. 22 - Among the most prevalent pathologies that afflict...Ch. 22 - Human geneticists have found the Finnish...Ch. 22 - Canavan disease, caused by homozygosity for a...Ch. 22 - In GWAS analysis, because of the existence of LD...Ch. 22 - In Fig. 22.15: a. Why do some chromosomes in the...Ch. 22 - Consider the triangle diagram shown in Fig. 22.17....Ch. 22 - Prob. 23PCh. 22 - You conduct a Case/Control study comparing the...Ch. 22 - Prob. 25PCh. 22 - ALS amyotrophic lateral sclerosis is a rare, fatal...Ch. 22 - Through GWAS explorations, scientists have...Ch. 22 - In domesticated dogs, size has a high...Ch. 22 - Suppose a GWAS investigation found a particular LD...Ch. 22 - In 2008, Time magazine named as its invention of...
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