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 4, Problem 48P
In 1995, doctors reported a Chinese family in which retinitis pigmentosa (progressive degeneration of the retina leading to blindness) affected only males. All six sons of affected males were affected, but all of the five daughters of affected males (and all of the children of these daughters) were unaffected.
| a. | What is the likelihood that this form of retinitis pigmentosa is due to an autosomal mutation showing complete dominance? |
| b. | What other possibilities could explain the inheritance of retinitis pigmentosa in this family? Which of these possibilities do you think is most likely? |
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In 1995, doctors reported a Chinese family in whichretinitis pigmentosa (progressive degeneration of theretina leading to blindness) affected only males. Allsix sons of affected males were affected, but all of thefive daughters of affected males (and all of thechildren of these daughters) were unaffected.a. What is the likelihood that this form of retinitispigmentosa is due to an autosomal mutationshowing complete dominance?b. What other possibilities could explain the inheritance of retinitis pigmentosa in this family? Whichof these possibilities do you think is most likely?
Susan’s grandfather was deaf, and passed down a hereditary form of deafness within Susan’s family as shown in Figure Q19–12.A. Is this mutation most likely to be dominant or recessive?B. Is it carried on an autosome or a sex chromosome? Why?C. A complete SNP analysis has been done for all of the 11 grandchildren (4 affected, and 7 unaffected). In comparing these 11 SNP results, how long a haplotype block would you expect to find around the critical gene? How might you detect it?
Suppose a man carries a very uncommon dominant mutation for a deadly muscular disease that doesn't show up until people are usually over 50 years of age (he has the disease). He and his wife are expecting their first child--a girl. What is the probability she will also have the disease if...
(1) it is autosomal(2) it is X-linked(3) it is Y-linked
Explain each answer in detail. Assume the penetrance of the trait is 100%.
Chapter 4 Solutions
Genetics: From Genes to Genomes
Ch. 4 - Choose the best matching phrase in the right...Ch. 4 - Humans have 46 chromosomes in each somatic cell....Ch. 4 - The figure that follows shows the metaphase...Ch. 4 - Human XX males who are sex-reversed because they...Ch. 4 - Researchers discovered recently that the sole...Ch. 4 - One oak tree cell with 14 chromosomes undergoes...Ch. 4 - Indicate which of the cells numbered iv matches...Ch. 4 - a. What are the four major stages of the cell...Ch. 4 - Answer the questions that follow for each stage of...Ch. 4 - Can you think of anything that would prevent...
Ch. 4 - One oak tree cell with 14 chromosomes undergoes...Ch. 4 - Which types of cell division mitosis, meiosis I,...Ch. 4 - Complete the following statements using as many of...Ch. 4 - The five cells shown in figure a e are all from...Ch. 4 - One of the first microscopic observations of...Ch. 4 - A person is simultaneously heterozygous for two...Ch. 4 - Assuming i that the two chromosomes in every...Ch. 4 - In the moss Polytrichum commune, the haploid...Ch. 4 - Can you think of anything that would prevent...Ch. 4 - Sister chromatids are held together through...Ch. 4 - The pseudoautosomal regions PARs of the X and Y...Ch. 4 - Remarkably, the platypus has 10 sex chromosomes,...Ch. 4 - Somatic cells of chimpanzees contain 48...Ch. 4 - In humans: a. How many sperm develop from 100...Ch. 4 - Women sometimes develop benign tumors called...Ch. 4 - In a certain strain of turkeys, unfertilized eggs...Ch. 4 - Imagine you have two pure-breeding lines of...Ch. 4 - A system of sex determination known as...Ch. 4 - In Drosophila, the autosomal recessive brown eye...Ch. 4 - Barred feather pattern is a Z-linked dominant...Ch. 4 - When Calvin Bridges observed a large number of...Ch. 4 - In a vial of Drosophila, a research student...Ch. 4 - In 1919, Calvin Bridges began studying an X-linked...Ch. 4 - In Drosophila, a cross was made between a...Ch. 4 - As we learned in this chapter, the white mutation...Ch. 4 - The following is a pedigree of a family in which a...Ch. 4 - Each of the four pedigrees that follow represents...Ch. 4 - The pedigree that follows indicates the occurrence...Ch. 4 - Duchenne muscular dystrophy DMD is caused by a...Ch. 4 - The X-linked gene responsible for DMD encodes a...Ch. 4 - Males have hemophilia when they are hemizygous for...Ch. 4 - In the Fast Forward Box Visualizing X Chromosome...Ch. 4 - Consider the following pedigrees from human...Ch. 4 - Several different antigens can be detected in...Ch. 4 - The ancestry of a white female tiger bred in a...Ch. 4 - The pedigree that follows shows the inheritance of...Ch. 4 - In 1995, doctors reported a Chinese family in...Ch. 4 - In cats, the dominant O allele of the X-linked...Ch. 4 - In marsupials like the opposum or kangaroo, X...Ch. 4 - The pedigree diagram below shows a family in which...
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