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
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 4, Problem 40P
The X-linked gene responsible for DMD encodes a protein called dystrophin that is required for muscle function. Dystrophin protein is not secreted—it remains in the cells that produce it. Given what you know about Barr body formation, do you think that females heterozygous for the recessive DMD disease allele could have the disease in some parts of their bodies and not others?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
What is a Barr body?
How many Barr bodies in a person with genotype XXXXX?
How is the structure of a Barr body different from that of other chromosomes in the cell?
How does the structure of a Barr body affect gene expression?
Color-blindness is an X-linked recessive trait. Heterozygous females are not color blind but they can sometimes have partial color blindness. Explain how this can occur.
In cells with more than one X chromosome, one X chromosome is inactivated. The opsin1 gene is on
the X chromosome and is expressed in the retinal cells of the eye. Mutations in this gene cause the
recessive trait of colorblindness. Most women who have one mutant allele of the opsin1 gene and
one normal allele of the opsin1 gene (they are heterozygous) can still see color. What is the most
likely explanation for this finding?
O Any mutations in the opsin1 gene on the active X can be corrected through genetic exchange (recombination)
with the inactive X
O If the active X has the mutant allele of opsin1 gene, the inactive X with the normal allele will be reactivated
The X with the mutant allele of the opsin1 gene is more likely to be inactivated because of the opsin1
mutation
Some retinal cells will have an active X with the mutant allele of the opsin1 gene, and some will have an active
X with the normal allele of the opsin1 gene
In man, muscular dystrophy is a condition in which the muscles waste away during early life and may result in a shorter life expectancy. It is due to a sex-linked, recessive gene. A certain couple has five children – three boys (ages 1yr, 3yrs, and 10yrs old) and two girls (ages 5yrs and 7yrs old). The oldest boy shows the symptoms of this disease. You are their family physician and they come to you for advice. What would you tell them about the chances of their other children developing the disease?
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...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Consider a couple: a woman who is homozygous for a recessive mutation that causes X-linked colorblindness, and a man with full color vision (he does not carry a copy of the mutation). a) What is the probability that a son of this couple will be colorblind? b) What is the probability that a daughter of the couple will be colorblind?arrow_forwardConsider a Droscophilia fly with a genotype of Nn XqYY. The dominant allele of the sex-linked gene specifies a black body and the recessive a white body. The recessive autosomal allele specifies hairy bristles while the dominant allele specifies smooth bristles. i)What is the ploidy of this fly? ii) What would the sex of this fly be? iii)What would the phenotype of this fly be with respect to these two loci?arrow_forwardLet’s suppose that two different X-linked genes exist in mice,designated with the letters N and L. Gene N exists in a dominant,normal allele and in a recessive allele, n, that is lethal. Similarly,gene L exists in a dominant, normal allele and in a recessive allele,l, that is lethal. Heterozygous females are normal, but males thatcarry either recessive allele are born dead. Explain whether or notit would be possible to map the distance between these two genesby making crosses and analyzing the number of living and deadoffspring. You may assume that you have strains of mice in whichfemales are heterozygous for one or both genes.arrow_forward
- Hemophilia is an X-linked recessive phenotype. Suppose a man who expresses the hemophilia phenotype has children with a woman who has the normal phenotype (and does not have a family history of hemophilia). If the couple have a son, what are the chances that he will have hemophilia? A) 50% B) 25% C) 0% D) 100%arrow_forwardRed-green color blindness is inherited as an X-linked recessive (Xc). If a color-blind man marries a woman who is heterozygous for normal vision, what would be the expected phenotypes of their children with reference to this character? In your answer, specify in your phenotype descriptions the gender of the children. (For example, don’t just say 75% of the children would be colorblind – you would instead say 100 % of the daughters would be colorblind and 50% of the sons would be colorblind. Note that this is not a correct answer; it is just to give you an idea of how to explain the correct phenotypes of the cross.)___arrow_forwardNormal vision (XA) in humans is dominant to color blindness (Xa) and is X-linked. A man with normal vision, whose father was colorblind, marries a colorblind woman. What are the chances that a son will be colorblind? What are the chances that a daughter will be colorblind? The determiner for brown eyes (B) is dominant to blue eyes (b) and is not X-linked. A colorblind man with brown eyes, whose mother was blue-eyed, marries a blue-eyed woman having normal vision, whose father was colorblind. Show the expected phenotypes ratio of their children involving eye color, color blindness, and sex.arrow_forward
- Males of many diploid species (like us) have X and Y sex chromosomes. They are hemizygous for most X- linked genes. Thus, males express most X-linked alleles, whether they are dominant or recessive in females. In the fruit fly Drosophila, it is common to achieve the equivalent of a test cross of X-linked genes in females by assessing the readily observed phenotypes of their male progeny. Since males do not receive X-linked genes from their father, sires of these crosses can be normal or wild-type flies. In fly genetics, it is conventional to name a gene after the mutant phenotype that enabled its discovery. Your challenge is to establish gene order and map distances between three X-linked genes in Drosophila. Each gene is represented by recessive mutant alleles that express rather distinctive phenotypes relative to their dominant wild-type alternative alleles. Flies expressing fruitless (f) are bisexual, lush (1) have a heightened responses to ethanol, and ken&barbie (kb) lack external…arrow_forwardAs shown in the Punnett square below, one variety of deafness is caused by an autosomal recessive allele. Two parents who do not show any signs of the disease but are carriers could therefore have a child who is deaf, because that child could inherit one recessive deafness-causing gene from each parent. Imagine that a deaf male mates with a hearing female. We know the deaf male must have the genotype dd, but the female could be either Dd or DD. Such a mating is essentially a testcross, like the one shown in Figure 9.10. If the parents’ first child has hearing, can you say with certainty what the mother’s genotype must be? What if the couple has four children (none twins), all with hearing—can you say with certainty the mother’s genotype? What would it take for a definitive genotype to be assigned?arrow_forwardProduce a Punnett square to illustrate the dihybrid cross described below: There are two common alleles for the TAS2R38 gene on Chromosome 7. This gene encodes a seven-transmembrane G-protein coupled receptor. This receptor controls the ability to taste glucosinolates. Phenylthiocarbamide (PTC) is a synthetic glucosinolate. The recessive TAS2R38 allele produces a non-functional receptor. The father in this dihybrid cross is heterozygous for these alleles, meaning that he can taste PTC. The mother is homozygous recessive, meaning that she cannot taste PTC The father has X-Linked Protoporphyria which means that he is very sensitive to sunlight exposure, he is hemizygous for the dominant causative mutation. The mother is homozygous wild type at the same locus. Add a file here showing your diagram.arrow_forward
- In Drosophila, the white gene located on the X chromosome affects eye color; an autosomal gene, wingless, is on an autosomal chromosome. Use the following allele symbols: Xw+ _ , Xw+Y = wild type red eyes; X-linked dominant allele Xw Xw , XwY = white eyes; X-linked recessive allele Y = Y sex chromosome vg+ = wild type wings; autosomal dominant vg = wingless; autosomal recessive Predict ratios/proportions of genotypes and phenotypes of offspring from the following cross, of a white-eyed male with wild type wings and a wild type red eyed female with wild type wings: indicate sex of offspring along with phenotypes. XwY vg+ vg x Xw+Xw vg+vgarrow_forwardNLFN3, a gene in the X chromosome has been linked to Autism spectrum disorder ASD. Research has shown that the mutation R451C (represented by the allele X+) is recessive and causes ASD. Ear lobes in humans are coded by a single gene which displays simple dominance. E results in free earlobes, and e corresponds to attached earlobes. What is the probability of having a female offspring with ASD symptoms and attached earlobes from X+Y Ee and X+X ee parents? 25% O 100% 0% O 75% O 12.5% O 50%arrow_forwardThe following pedigree represents the inheritance of an autosomal recessive disease in a certain family. 2 5 2 4 5 8 3 4. 6. 1 1- How many males are affected by the disease? 3- How many children did the couple Il-4 and Il-5 have? 4- How many sisters did III-8 have? 5- What is the genotype of III-8? 40arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSON
Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax
Anatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
Animal Communication | Ecology & Environment | Biology | FuseSchool; Author: FuseSchool - Global Education;https://www.youtube.com/watch?v=LsMbn3b1Bis;License: Standard Youtube License