Human Heredity: Principles and Issues (MindTap Course List)
Human Heredity: Principles and Issues (MindTap Course List)
11th Edition
ISBN: 9781305251052
Author: Michael Cummings
Publisher: Cengage Learning
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 10, Problem 6QP
Summary Introduction

To determine: The possible genotypes of children born if a individual who is heterozygous for a recessive mutation in enzyme 1 and enzyme 2 marries an individual having the same genotype.

Introduction: Metabolic pathways are catalyzed using enzymes. These enzymes are synthesized based on information provided by the genes.. Any type of change in these genes can hinder the synthesis of these enzymes or lead to synthesis of faulty enzymes. Heterozygosity is when same copies of alleles are present for a gene and homozygosity is when different copies of alleles are present for a gene.

Expert Solution
Check Mark

Explanation of Solution

It is given that both the individuals are heterozygous for a recessive mutation of enzymes 1 and 2. To find the possible genotypes of their children, genotypes of parents can be assumed as:

R represents normal enzyme 1 and r shows mutated enzyme 1. D shows normal enzyme 2 and d shows mutated enzyme 2.

Both the parents are heterozygous for the recessive mutation in both the enzymes. So the gametes produced by these parents will be RD, Rd, rD, and rd.

Genotype of the children from these gametes can be determined as follows:

 RDRdrDrd
RDRRDDRRDdRrDDRrDd
RdRRDdRRddRrDdRrdd
rDRrDDRrDdrrDDrrDd
rdRrDdRrddrrDdrrdd

GenotypesRRDD, RRDd, RrDD, RrDd, RRDd, RrDd, RrDD, RrDd, and RrDd will not show any mutation in any of the enzymes.

Genotypes rrDD, rrDd, and rrDd will show mutation in enzyme 1 only.

Genotypes RRdd, Rrdd, and Rrdd will show mutation in enzyme 2 only.

Genotype rrdd will show mutation in both the enzymes 1 and 2.

Summary Introduction

To determine: The activity ofenzyme 1 and enzyme 2 for all the genotypes that are produced in children if an individual who is heterozygous for a recessive mutation in both, enzyme 1 and enzyme 2, marries an individual having the same genotype, assuming that there is 0% activity for mutant alleles and 50% activity in normal alleles.

Introduction: Metabolic pathways are catalyzed using enzymes. These enzymes are synthesized based on information provided by the genes.. Any type of change in these genes can hinder the synthesis of these enzymes or lead to synthesis of faulty enzymes. Heterozygosity is when same copies of alleles are present for a gene and homozygosity is when different copies of alleles are present for a gene.

Expert Solution
Check Mark

Explanation of Solution

The possible genotypes of children born from parents who are heterozygous for a recessive mutation in both the enzymes are determined as follows:

R represents normal enzyme 1 and r shows mutated enzyme 1. D shows normal enzyme 2 and d shows mutated enzyme 2.

Both the parents are heterozygous for the recessive mutation in both the enzymes. So the gametes produced by these parents will be RD, Rd, rD, and rd.

Genotype of the children from these gametes can be determined as follows:

 RDRdrDrd
RDRRDDRRDdRrDDRrDd
RdRRDdRRddRrDdRrdd
rDRrDDRrDdrrDDrrDd
rdRrDdRrddrrDdrrdd

Genotypes RRDD, RRDd, RrDD, RrDd, RRDd, RrDd, RrDD, RrDd, and RrDd will not show any mutation in any of the enzymes. Hence, both the enzymes will show 50% activity in these genotypes

Genotypes rrDD, rrDd, and rrDd will show mutation in enzyme 1 only. Hence, in children with these genotypes, enzyme 1 will show 0% activity and enzyme 2 will show 50 % activity.

Genotypes RRdd, Rrdd, and Rrdd will show mutation in enzyme 2 only. Hence, in children with these genotypes, enzyme 1 will show 50% activity and enzyme 2 will show 0% activity.

Genotype rrdd will show mutation in both the enzymes 1 and 2. Hence, in children with these genotypes, both, enzyme 1 and enzyme 2 will show 0% activity.

Summary Introduction

To determine: Whether compound C will be made or not in each genotype of children born, if an individual who is heterozygous for a recessive mutation in both, enzyme 1 and enzyme 2, marries an individual having the same genotype, and if compound C not produced, the compounds that will be in excess.

Introduction: Metabolic pathways are catalyzed using enzymes. These enzymes are synthesized based on information provided by the genes.. Any type of change in these genes can hinder the synthesis of these enzymes or lead to synthesis of faulty enzymes. Heterozygosity is when same copies of alleles are present for a gene and homozygosity is when different copies of alleles are present for a gene.

Expert Solution
Check Mark

Explanation of Solution

Genotype RRDD will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts.

Genotype RRDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts.

Genotype RrDD will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype RrDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype RRDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype RRdd will show mutation in enzyme 2 only. Hence, compound C will not be produced while there will be an excess production of compound B. Compound A will be present in normal amounts.

Genotype RrDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype Rrdd will show mutation in enzyme 2 only. Hence, compound C will not be produced while there will be an excess production of compound B. Compound A will be present in normal amounts.

Genotype RrDD will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype RrDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype rrDD will show mutation in enzyme 1 only. So there will be no production of compound B as mutated enzyme 1 will not be able to act on compound A. Absence of compound B will cause no production of compound C. Here, compound A will be present in excess.

Genotype rrDd will show mutation in enzyme 1 only. So there will be no production of compound B as mutated enzyme 1 will not be able to act on compound A. Absence of compound B will cause no production of compound C. Here, compound A will be present in excess.

Genotype RrDd will not show any mutation in any of the enzymes. So, all the compounds will be present in their adequate amounts

Genotype Rrdd will show mutation in enzyme 2 only. Hence, compound C will not be produced while there will be an excess of compound B. Compound A will be present in normal amounts.

Genotype rrDd will show mutation in enzyme 1 only. So there will be no production of compound B as mutated enzyme 1 will not be able to act on compound A. Absence of compound B will cause no production of compound C. Here, compound A will be present in excess.

Genotype rrdd will show mutation in both, enzyme 1 and enzyme 2. Hence no compound will be metabolized and compound C will not be produced.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Lesch-Nyhan syndrome is due to a mutation in a gene that encodesa protein called hypoxanthine-guanine phosphoribosyltransferase(HPRT). HPRT is an enzyme that functions in purine metabolism.People afflicted with this syndrome have severe neurodegenerationand loss of motor control. The pedigree below contains severalindividuals with Lesch-Nyhan syndrome, shown with blacksymbols. Based on this pedigree, does this syndrome appearto be inherited by an autosomal recessive, autosomal dominant,X-linked recessive, or X-linked dominant pattern? Explainyour reasoning.
Leber's Hereditary Optic Neuropathy (LHON) is a disease that involves degeneration of neural cells in the retina and results in loss of central vision. The disease is caused by mutations in any one of three genes in the mitochondrial genome that encode proteins involved in oxidative phosphorylation. In a genetic counseling clinic, a woman and her husband seek advice on the potential that any of their children would be afflicted with LHON. The husband's mother and father, both exhibit symptoms of the disease, but the woman does not. What is a reasonable advising statement to make? There is not enough information to advise this couple. a. The couple should be advised that all of their children are likely to display symptoms of LHON. b. The couple should be advised that all their female children will display symptoms of LHON, but male children will be unaffected. C. The couple should be advised that all their male children will display symptoms of LHON, but female children will be…
Leber’s Hereditary Optic Neuropathy (LHON) is a disease that involves degeneration of neural cells in the retina and results in loss of central vision. The disease is caused by mutations in any one of three genes in the mitochondrial genome that encode proteins involved in oxidative phosphorylation. In a genetic counseling clinic, a woman and her husband seek advice on the potential that any of their children would be afflicted with LHON. The husband's mother and father, both exhibit symptoms of the disease, but the woman does not. What is a reasonable advising statement to make?  a. The couple should be advised that all of their children are likely to display symptoms of LHON.   b. There is not enough information to advise this couple.   c. The couple should be advised that none of their children will be affected.   d. The couple should be advised that all their male children will display symptoms of LHON, but female children will be unaffected.   e. The couple should be…
Knowledge Booster
Background pattern image
Biology
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
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
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