Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 15, Problem 1CS
Six months pregnant, an expectant mother had a routine ultrasound that showed that the limbs of the fetus were unusually short. Her physician suspected that the baby might have a genetic form of dwarfism called achondroplasia, an autosomal dominant trait occurring with a frequency of about 1 in 27,000 births. The parents were directed to a genetic counselor to discuss this diagnosis. In the conference, they learned that achondroplasia is caused by a mutant allele. Sometimes it is passed from one generation to another, but in 80 percent of all cases it is the result of a spontaneous mutation that arises in a gamete of one of the parents. They also learned that most children with achondroplasia have normal intelligence and a normal life span.
What information would be most relevant to concluding which of the two mutation origins, inherited or new, most likely pertains in this case? How does this conclusion impact on this couple's decision to have more children?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Six months pregnant, an expectant mother had a routine ultrasound that showed that the limbs of the fetus were unusually short. Her physician suspected that the baby might have a genetic form of dwarfism called achondroplasia, an autosomal dominant trait occurring with a frequency of about 1 in 27,000 births. The parents were directed to a genetic counselor to discuss this diagnosis. In the conference, they learned that achondroplasia is caused by a mutant allele. Sometimes it is passed from one generation to another, but in 80 percent of all cases it is the result of a spontaneous mutation that arises in a gamete of one of the parents. They also learned that most children with achondroplasia have normal intelligence and a normal life span. 1. What information would be most relevant to concluding which of the two mutation origins, inherited or new, most likely pertains in this case? How does this conclusion impact on this couple’s decision to have more children? 2. It has been…
A young lady requested pre-marital genetic counselling because her sister had died in infancy of gangliosidosis, an autosomal recessive disease. What is the risk that this young lady has similarly affected offspring? What advice should be given?
A couple is planning a family, but since each has a brother having the sickle-cell disorder, they are worried that their kids might develop the disorder too. Neither of them nor their respective parents have the disorder. Which of the following will be your smartest advice as a genetic counsellor?
One of four of their children can be expected to have sickle cell.
It is possible that none of their kids will have the disorder, but tests should be carried out on both of them to confirm.
All of their children will have sickle-cell disorder.
There is no chance of any of their kids having sickle cell.
Chapter 15 Solutions
Concepts of Genetics (12th Edition)
Ch. 15 - If a point mutation occurs within a human egg cell...Ch. 15 - One of the most famous cases of an X-linked...Ch. 15 - The cancer drug melphalan is an alkylating agent...Ch. 15 - Geneticists often use the alkylating agent...Ch. 15 - Six months pregnant, an expectant mother had a...Ch. 15 - Six months pregnant, an expectant mother had a...Ch. 15 - HOW DO WE KNOW? In this chapter, we focused on how...Ch. 15 - CONCEPT QUESTION Review the Chapter Concepts list...Ch. 15 - What is a spontaneous mutation, and why are...Ch. 15 - Prob. 4PDQ
Ch. 15 - Prob. 5PDQCh. 15 - Why is a random mutation more likely to be...Ch. 15 - Most mutations in a diploid organism are...Ch. 15 - What is the difference between a silent mutation...Ch. 15 - Describe a tautomeric shift and how it may lead to...Ch. 15 - Contrast and compare the mutagenic effects of...Ch. 15 - Why are frameshift mutations likely to be more...Ch. 15 - Why are X rays more potent mutagens than UV...Ch. 15 - DNA damage brought on by a variety of natural and...Ch. 15 - Contrast the various types of DNA repair...Ch. 15 - Mammography is an accurate screening technique for...Ch. 15 - A significant number of mutations in the HBB gene...Ch. 15 - Describe how the Ames test screens for potential...Ch. 15 - Prob. 18PDQCh. 15 - Compare DNA transposons and retrotransposons. What...Ch. 15 - Prob. 20PDQCh. 15 - In maize, a Ds or Ac transposon can alter the...Ch. 15 - Prob. 22PDQCh. 15 - In a bacterial culture in which all cells are...Ch. 15 - Presented here are hypothetical findings from...Ch. 15 - Prob. 25ESPCh. 15 - Prob. 26ESPCh. 15 - What evidence indicates that mutations in human...Ch. 15 - Among Betazoids in the world of Star Trek, the...Ch. 15 - Skin cancer carries a lifetime risk nearly equal...Ch. 15 - It has been noted that most transposons in humans...Ch. 15 - Mutations in the IL2RG gene cause approximately 30...
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
- A proband female with an unidentified disease seeks the advice of a genetic counselor before starting a family. Based on the following data, the counselor constructs a pedigree encompassing three generations: (1) The maternal grandfather of the proband has the disease. (2) The mother of the proband is unaffected and is the youngest of five children, the three oldest being male. (3) The proband has an affected older sister, but the youngest siblings are unaffected twins (boy and girl). (4) All the individuals who have the disease have been revealed. Duplicate the counselors featarrow_forwardSix months pregnant, an expectant mother had a routineultrasound that showed that the limbs of the fetus wereunusually short. Her physician suspected that the babymight have a genetic form of dwarfism called achondroplasia,an autosomal dominant trait occurring with a frequency of about1 in 27,000 births. The parents were directed to a genetic counselorto discuss this diagnosis. In the conference, they learnedthat achondroplasia is caused by a mutant allele. Sometimes itis passed from one generation to another, but in 80 percent ofall cases it is the result of a spontaneous mutation that arisesin a gamete of one of the parents. They also learned that mostchildren with achondroplasia have normal intelligence and a normallife span. What information would be most relevant to concluding whichof the two mutation origins, inherited or new, most likelypertains in this case? How does this conclusion impact on thiscouple’s decision to have more children?arrow_forwardSix months pregnant, an expectant mother had a routineultrasound that showed that the limbs of the fetus wereunusually short. Her physician suspected that the babymight have a genetic form of dwarfism called achondroplasia,an autosomal dominant trait occurring with a frequency of about1 in 27,000 births. The parents were directed to a genetic counselorto discuss this diagnosis. In the conference, they learnedthat achondroplasia is caused by a mutant allele. Sometimes itis passed from one generation to another, but in 80 percent ofall cases it is the result of a spontaneous mutation that arisesin a gamete of one of the parents. They also learned that mostchildren with achondroplasia have normal intelligence and a normallife span. It has been suggested that prenatal genetic testing for achondroplasiabe made available and offered to all women. Wouldyou agree with this initiative? What ethical considerationswould you consider when evaluating the medical and societalconsequences of offering…arrow_forward
- Marfan syndrome is a disease caused by a rare dominant allele of the fibrillin-1 gene. Fibrillin-1 is an important component of the extracellular matrix, and people with the disease-causing allele have abnormal connective tissue. An affected mother (Marta) and an unaffected father (Joe) have one unaffected daughter (Luisa - she does not exhibit any traits of the syndrome). If Luisa has a child with Nico (unaffected), what is the probability that her child will inherit Marfan syndrome? Select one: a. 50% b. 25% c. 100% d. 0% e. 75%arrow_forwardIn a particular country in sub-Saharan Africa, a medical study revealed that 0.075% of the country's population are suffering from sickle-cell anemia. Sickle cell disease is caused by a mutation in the haemoglobin-Beta gene found on chromosome 11. Sickle cell anemia is controlled by a pair of alleles, H and h, where the individuals with the illness have the homozygous recessive genotype; those with normal red blood cells have the alternative genotype. Using the Hardy-Weinberg's equation, calculate the percentage of the population of the two genotypes for normal blood cells. In a few remote areas in that country, the percentage of sickle cell anemia reaches as high as 5%. Calculate the percentage of homozygous and heterozygous individuals with the normal blood cells and find the ratio for both phenotypes.arrow_forwardTay Sachs is a rare autosomal recessive disorder that causes mental and physical disabilities leading to death in infants. Affected individuals are lacking the enzyme hexosaminidase, causing lipids to build up in the brain.The HEXA gene on chromosome 15 codes for hexosaminidase, and a four base pair insertion in the gene results in an altered reading frame and non-functional enzyme being produced. Individuals who are carriers (heterozygotes) of the Tay-Sachs allele are not affected by the disease but appear to have increased protection against tuberculosis.The incidence of Tay-Sachs disease is much higher among Ashkenazi Jews originating from Eastern Europe than the general population of the United States. About 1 in 3 500 babies of Ashkenazi Jewish heritage are born with Tay-Sachs disease and about 1 in 30 Ashkenazi Jews are carriers compared to about 1 in 320 000 babies born with the disease and about 1 in 300 carriers in the general United States population. Ashkenazi Jews living in…arrow_forward
- Take the example of B-thalassemia, an autosomal recessive genetic disease that particularly affects people from around the Mediterranean. This disease is associated with an anomaly of hemoglobin, a protein essential for the transport of oxygen, which is composed of four chains: two alpha (a) and two beta (B). In case of B-thalassemia, the ẞ chains are produced in insufficient or no quantity in an individual homozygous recessive resulting in insufficient production of overall hemoglobin leading to anemia and other physiological challenges. The gene that controls the synthesis of the ẞ chains is located on chromosome 11. Here is part of the coding portion of this gene (which controls a total of 146 amino acids and of which you only see the portion 36 to 41) and one of the targeted mutations: 1. Give the sequence of amino acids from the template and mutated strands. 2. What type of point mutation is it? 3. Using the principles of the theory of evolution, explain briefly and generally why…arrow_forwardThe pedigree below shows that inheritance of a disease that is caused by a late onset, dominant, autosomal mutation that is rare, but only 50% penetrant. The gene that is mutated in the disease is linked at a distance of 10 cm to a microsatellite marker that has alleles numbered 1, 2, and 3. The marker alleles detected in each individual are indicated below. What is the probability that individual A will develop the disease? Explain using an illustration of this occurs.arrow_forwardA condition known as icthyosis hystrix gravior appeared in a boy in the early eighteenth century. His skin became very thick and formed loose spines that were sloughed off at intervals. When he grew up, this “porcupine man” married and had six sons, all of whom had this condition, and several daughters, all of whom were normal. For four generations, this condition was passed from father to son. From this evidence, what can you postulate about the location of the gene?arrow_forward
- Phenylketonuria (PKU) is a disease that results from a recessive gene.Suppose that two unaffected parents produce a child with PKU. a. What is the probability that a sperm from the father will contain the PKU allele?b. What is the probability that an egg from the mother will contain the PKU allele?c. What is the probability that their next child will have PKU?d. What is the probability that their next child will be heterozygous for the PKU gene?arrow_forwardPhenylketonuria (PKU) is a disease that results from a recessive gene. Suppose that two unaffected parents produce a child with PKU. a. What is the probability that a sperm from the father will contain the PKU allele? b. What is the probability that an egg from the mother will contain the PKU allele? c. What is the probability that their next child will have PKU? d. What is the probability that their next child will be heterozygous for the PKU gene?arrow_forwardThe following pedigree illustrates the inheritance of Nance–Horan syndrome, a rare genetic condition in which affected people have cataracts and abnormally shaped teeth.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
Human Heredity: Principles and Issues (MindTap Co...
Biology
ISBN:9781305251052
Author:Michael Cummings
Publisher:Cengage Learning
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY