Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 23, Problem 13EQ
In the Human Genome Project, researchers have collected linkage data from many crosses in which the male was heterozygous for molecular markers and many crosses where the female was heterozygous for the markers. The distance between the same two markers, computed in map units, is different between males and females. In other words, the linkage maps for human males and females are not the same. Propose an explanation for this discrepancy. Do you think the sizes of chromosomes (excluding the Y chromosome) in human males and females are different? How could physical mapping resolve this discrepancy?
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In the Human Genome Project, researchers have collectedlinkage data from many crosses in which the male washeterozygous for molecular markers and many crosses wherethe female was heterozygous for the markers. The distancebetween the same two markers, computed in map units, isdifferent between males and females. In other words, thelinkage maps for human males and females are not the same.Propose an explanation for this discrepancy. Do you think thesizes of chromosomes (excluding the Y chromosome) in humanmales and females are different? How could physical mappingresolve this discrepancy?
To determine the recombination frequency between body color and wing genes in flies, you perform several crosses where you cross an F1 having red body and smooth wings with a yellow-bodied, crinkle-winged fly. You get the following results. What is the distance between the genes for body color and wing surface in map units?
Consider the first category of test-cross offspring shown in figure 8.2 (+b, LS). Consider also that the parents of the heterozygous female flies in the test cross had the following genotypes: bb, SS, and +, LL.
A. What would be the physical phenotype of these flies?
B. If PC was conducted with the DNA of one of these flies using the primers for the molecular marker, what would be the appearance of the bands on an electrophoresis gel with the PC products?
C. If the gene for black body and the locus for the molecular marker (L long or S short) were unlinked, what proportion of the test-cross progeny would be black flies that are heterozygous for the molecular marker? What proportion would be flies with normal body color, which are homozygous for one form of the molecular marker?
D. If the gene for black body and the locus for the molecular marker were linked, how would the proportion of flies be different?
Chapter 23 Solutions
Genetics: Analysis and Principles
Ch. 23.1 - Prob. 1COMQCh. 23.2 - Prob. 1COMQCh. 23.3 - A molecular marker is a _____ found at a specific...Ch. 23.3 - 2. Which of the following is an example of a...Ch. 23.3 - To map the distance between molecular markers via...Ch. 23.4 - 1. What is a contig?
a. A fragment of DNA that...Ch. 23.4 - A vector that can carry a large fragment of...Ch. 23.4 - 3. Chromosomal walking is a method of _____ in...Ch. 23.5 - Prob. 1COMQCh. 23.5 - Prob. 2COMQ
Ch. 23.5 - 3. A prokaryotic genome is about 4 million bp in...Ch. 23.6 - Metagenomics is aimed at a. determining the...Ch. 23 - 1. A person with a rare genetic disease has a...Ch. 23 - For each of the following, decide if it could be...Ch. 23 - Which of the following statements about molecular...Ch. 23 - 1. Is each of the following a method used in...Ch. 23 - Prob. 2EQCh. 23 - Prob. 3EQCh. 23 - The cells from a persons malignant tumor were...Ch. 23 - 5. Figure 23.2 describes the technique of FISH....Ch. 23 - Explain how DNA probes with different fluorescence...Ch. 23 - 7. A researcher is interested in a gene found on...Ch. 23 - Prob. 8EQCh. 23 - Prob. 9EQCh. 23 - Prob. 10EQCh. 23 - Prob. 11EQCh. 23 - Prob. 12EQCh. 23 - In the Human Genome Project, researchers have...Ch. 23 - 14. Take a look at question 3 in More Genetic...Ch. 23 - 15. Place the following stages of a physical...Ch. 23 - 16. What is an STS? How are STSs generated...Ch. 23 - 17. Four cosmid clones, which we will call cosmids...Ch. 23 - A human gene, which we will call geneX, is located...Ch. 23 - 19. Describe how you would clone a gene by...Ch. 23 - 20. A bacterium has a genome size of 4.4 Mb. If a...Ch. 23 - 21. Discuss the advantages of next-generation...Ch. 23 - Prob. 22EQCh. 23 - Prob. 23EQCh. 23 - What is a molecular marker? Give two examples....Ch. 23 - Which goals of the Human Genome Project do you...
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