Genetics: From Genes To Genomes (6th International Edition)
6th Edition
ISBN: 9781260041217
Author: Leland Hartwell Dr., ? Michael L. Goldberg Professor Dr., ? Janice Fischer, ? Leroy Hood Dr.
Publisher: Mcgraw-Hill
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 10, Problem 26P
Certain individuals with mild forms of β-thalassemia produce, in addition to normal adult hemoglobin with two α chains and two β chains, lower levels of an unusual, so-called Lepore hemoglobin with two α chains and two chains in each of which the N-terminal half comes from a normal δ chain and the C-terminal half comes from a normal β chain. Certain other individuals who are asymptomatic produce a different, unusual anti-Lepore hemoglobin that contains two α chains and two chains in which the N-terminal half comes from a normal β chain and the C-terminal half comes from a normal δ chain.
| a. | Describe an event that could give rise to both Lepore and anti-Lepore hemoglobins |
| b. | Are the mildly thalassemic individuals with Lepore hemoglobin homozygotes or heterozygotes for the unusual allele? |
| c. | Why might these mildly thalassemic people produce less Lepore hemoglobin than normal adulthemoglobin? |
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A very new Hemoglobin variant, called Hb simplex, has just been identified in patients with hypoxia (i.e. patients for whom the oxygenation of organs is not properly accomplished). However, this variant is able to bind dioxygen with a Kd which is significantly lower to that of Hemoglobin from normal patients. This effect has been associated with the substitution of a Lys by a Met at two distinct sites of the b subunit of Hemoglobin : one site close to the N-terminus, and the other site close to the C-terminus of the polypeptide chain. Most importantly, these 2 sites are known to be involved in the maintain of the physical interactions between the subunits a and b in Hemoglobin.
1) The aforementioned Hb simplex mutations lead to a loss of physical interactions between the subunits a and b. What type(s) of chemical bonds between the 2 subunits (i.e. covalent, electrostatic, ion-dipole, dipole-dipole, van der waals) would you hypothesize to be affected by these mutations? explain.
2)…
In one type of hemoglobin variant, lysine EF6 is replaced by an aspartic acid residue.
What would be the effects of this mutation on the affinity of the hemoglobin for 2,3
BPG and oxygen?
The affinity for 2,3-BPG would increase, and for oxygen would decrease.
The affinity for 2,3-BPG would decrease, and for oxygen would decrease.
The affinities for 2,3-BPG and for oxygen would be unaffected.
The affinity for 2,3-BPG would increase, and for oxygen would increase.
The affinity for 2,3-BPG would decrease, and for oxygen would increase.
Hydroxyurea has been shown to increase the expression of fetal hemoglobin in adult red blood cells, by a mechanism that remains unclear. Explain why hydroxyurea can be a useful therapy for patients with sickle-cell anemia.
Chapter 10 Solutions
Genetics: From Genes To Genomes (6th International Edition)
Ch. 10 - Prob. 1PCh. 10 - List three independent techniques you could use to...Ch. 10 - Figure 10.2a has numbers indicating the...Ch. 10 - Which of the enzymes from the following list would...Ch. 10 - Prob. 5PCh. 10 - a. What sequence information about a gene is...Ch. 10 - Why do geneticists studying eukaryotic organisms...Ch. 10 - Consider three different kinds of human libraries:...Ch. 10 - The human genome has been sequenced, but we still...Ch. 10 - This problem investigates issues encountered in...
Ch. 10 - For the sake of simplicity, Fig. 10.4 omitted one...Ch. 10 - Give two different reasons for the much higher...Ch. 10 - Using a cDNA library, you isolated two different...Ch. 10 - The figure that follows shows part of a modified...Ch. 10 - In Problem 14, cDNAs F and G could not be found in...Ch. 10 - Fig. 10.10 presents a model for exon shuffling in...Ch. 10 - An interesting phenomenon found in vertebrate DNA...Ch. 10 - a. If you found a zinc-finger domain which...Ch. 10 - Prob. 19PCh. 10 - In the human immune system, so-called B cells can...Ch. 10 - Chimpanzees have a set of hemoglobin genes very...Ch. 10 - Complete genome sequences indicate that the human...Ch. 10 - On your computers browser, view the page accessed...Ch. 10 - Prob. 24PCh. 10 - Prob. 25PCh. 10 - Certain individuals with mild forms of...Ch. 10 - The 1 and 2 genes in humans are identical in their...Ch. 10 - Prob. 28P
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
- Certain naphthalene derivatives, such as the dansyl group, exhibit a weak yellow fluorescence when they are in a highly polar environment (such as water) and an intense blue fluorescence when they are in a markedly nonpolar environment (such as hexane). The binding of ´ -dansyl-lysine to specific antibody is accompanied by a marked increase in its fluorescence intensity and a shift in color from yellow to blue. What does this finding reveal about the hapten–antibody complex?arrow_forwardThe proximal histidine residues have been replaced by glycine residues by mutation of the cloned genes for both the α and β subunits of hemoglobin. With the tetrameric mutant hemoglobin (all subunits being mutant, α H F8 G, β H F8 G), it was found that the “proximal” coordination bonds to hemes in the mutant protein could be replaced by having the small molecule imidazole in the buffers. Oxygen binding curves for the tetrameric mutant hemoglobin were measured. A. The degree of cooperativity in oxygen binding for the mutant hemoglobin (with imidazole present) would be expected to 1) increase 2) decrease 3) not be affected) compared with the normal protein. B. Justify your answer to part A in terms of what you know about the structural basis of cooperativity in hemoglobin. C. How would the Hill coefficient for the mutant be expected to change compared with nH for normal hemoglobin, which is ~3?arrow_forwardWhen human hemoglobin undergoes a mutation, the mutant protein usually does not replace all of the normal HbA in the red blood cells or erythrocytes of the individual. The erythro- cytes contain mixtures of varying amounts of both HbA and the mutant protein depending on the mutation and the individual. Hb Yakima is a mutant human Hb with an Asp-(B99)His mutation. The diagram on the right shows that Hb Yakima was separated by DEAE-cellulose chromatography from HbA with a 0 – 0.1 M linear gradient of NaCl buffered to pH 8.3. Why is chromatog- raphy carried out at pH 8.3? If the isoelectric point of HbA is 6.85, what is the change in total charge caused by the mutation?How does the change in charge explain the chromatography elution profile of the Hb Yakima/HbA mixture? 1,5 -Hb-A Hb -Yakima 1.0 0.5- 20 40 60 80 00 Fraction number O.D578 nmarrow_forward
- Suggest probable consequences of the following real or possible hemoglobinmutations. [Note: as shown](a) At β146 (HC3) His → Asp(b) At β92 (F8) His → LeuIn each case, indicate whether a single-nucleotide change is sufficient forthe mutation.arrow_forwardHow does HbS aggregation occur in sickle-cell anemia? Place the steps in the correct order. Note that deoxyhemoglobin is in the T state; oxyhemoglobin is in the R state. No aggregation R state Hb shifts to T state Hb. Sickled red blood cell Answer Bank Val interacts with the pocket of a ß chain on another HbS. Additional T state HbS interact with the growing aggregate to form an insoluble fiber. [0₂] decreases due to vigorous exercise or high altitude.arrow_forwardThe SARS-CoV-2 spike (S) protein and its sugars have been the subject of much scientific investigation. S protein, the main focus of SARS-CoV-2 vaccine development, is heavily glycosylated. In fact, it contains 22 N-linked, and at least two O-linked, glycosylation sites. Which of the following statements is most likely to describe this glycosylation process? a.) The SARS-CoV-2 spike protein is probably glycosylated in both the lysosomes and Golgi apparatus of cells in the respiratory tract of an infected subject. b.) The SARS-CoV-2 spike protein is probably glycosylated in both the endoplasmic reticulum and proteasomes of cells in the respiratory tract of an infected subject. c.) The SARS-CoV-2 spike protein is probably glycosylated in both the endoplasmic reticulum and Golgi apparatus of cells in the respiratory tract of an infected subject.arrow_forward
- What is the molecular basis for methicillin resistance in certain strains of S. aureus (MRSA)?arrow_forwardWhat is the dominant biochemical activity or molecular interaction that Sickle Cell Anemia Hemoglobin Subunit beta-protein (P68871) is predicted to carry out?arrow_forwardThe group of disorders associated with single gene mutations affecting amino acid sequences in the alpha and beta globin genes are called Question 10 options: A) thalassemias B) hemoglobinopathies C) hemolytic anemias D) megaloblastic anemiasarrow_forward
- Fetal hemoglobin comprises of αγ sub-units. It has been found that the γ-chain contains serine at position 143 instead of Histidine 143 normally found in the β-chain. The amino acid 143 lines the DPG binding site. This mutation in the γ chain results in a) Increased Oxygen binding in the fetus. b) Increased efficiency of oxygen transport to the lungs in the fetus. c) Increased DPG binding in the fetal hemoglobin d) This is a silent mutation, i.e. no change should be observed.arrow_forwardThe haemoglobin proteins of RNA polymerase ii sub units RPB1-P24928 RPB2-P30876 RPB3-P19387 RPB4-015514 are they similar? Explain?arrow_forwardYou have the following reagents available Rat anti-Keratin 8 antibody specific for mouse Keratin 8, Rabbit polyclonal antibody against mouse keratin 5 and antifade reagent with DAPI to stain DNA. Both primary antibodies work best at 1:500 dilution. A) What additional reagents would you need to perform immunostaining of frozen sections of mouse thymus tissue for Keratin 8 that is expressed in cortical thymic epithelial cells and Keratin 5 that is expressed in mouse medullary thymic epithelial cells? B) Create a staining protocol including all tubes and appropriate controls to stain 4 slides with frozen thymic sections. You will need 200ul of antibody staining solution for each slide.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