Concept explainers
To review:
The way in which variable penetrance of the Diamond Blackfan Anemia (DBA) can help in studying the molecular events that cause the disorder.
Introduction:
DBA is classified as an autosomal dominant disorder that is caused by a mutation in one of the 11 genes that code for ribosomal proteins. An individual suffering from this disease is born with birth defects, bone marrow failure, and also has a tendency to develop cancer.
Genetic disorders are caused by the abnormalities of the genome. These disorders are inherited as the genetic information from both the parents is passed down to the progeny. DBA is caused by a mutation in the genes that code for ribosomal protein. The symptoms of this disorder vary from individual to individual. Some of them include fast heartbeat, heart murmur, a pale skin, and birth defects, such as abnormality of the hands, heart, face, kidneys, head, or genital area.
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Essentials of Genetics (9th Edition) - Standalone book
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- Discuss Concepts A mutation occurs that alters an anticodon in a tRNA from 3-AAU-5 to 3-AUU-5. What effect will this mutation have on protein synthesis?arrow_forwardIPSCs are nearly identical to human embryonic stem cells in terms of gene expression, but there may be other ways in which they are not equivalent. For example, the telomeres of IPSCs often vary in length, with many IPSCs cells having telomeres shorter than those of embryonic. How might shortened telomeres affect the life-span of IPSCs or of differentiated cells derived from them?arrow_forwardDiscuss Concepts The normal form of a gene contains the nucleotide sequence: When this gene is transcribed, the result is the following mRNA molecule: In a mutated form of the gene, two extra base pairs (underlined) are inserted: What effect will this particular mutation have on the structure of the protein encoded in the gene?arrow_forward
- (5) AAG a. What is indicated by label (2) in the figure above? b. What is indicated by label (3) in the figure above? c. What is the function of part d. Which amino acid is represented by (6)? e. Give the one anticodon in the 5' to 3' direction that will recognize all the codons for this amino acid in (c).arrow_forwardmutation 5' 1 3' 5' 3' 5' 3' 4 3 Mutations in splice sites can lead to the formation of abnormal proteins. The diagram illustrates a mutation in the 3' splice site between exons 1 and 2 which prevents binding of snRNPs to that site. Which of the following consequences could be a result of this mutation? 1. The mutant mRNA contains intronic sequences. 2. The mutant MRNA is shorter compared to wild-type (original) MRNA. 3. The mutant MRNA produces a longer protein compared to wild-type (original) MRNA. 4. The mutant MRNA has exon 2 deleted. O A. 1, 2 and 3 O B. 1 and 3 O C. 2 and 4 D. 4 only O E. All of 1, 2, 3 and 4 are correctarrow_forward. Geneticists interested in human hemoglobins havefound a very large number of mutant forms. Some ofthese mutant proteins are of normal size (but haveamino acid substitutions) while others are short, dueto deletions or nonsense mutations. The first extralong example was named Hb Constant Spring, inwhich the β-globin has all of its normal amino acidsplus several extra amino acids attached after thenormal C-terminal end of the protein. a. What is the most plausible explanation forits origin?b. Is it possible that Hb Constant Spring arose fromfailure to splice out an intron?c. Estimate how many extra amino acids mightbe added to the C terminal end of the mutantproteinarrow_forward
- 1. Certain proteins that stimulate expression of a gene bind to DNA in a sequence specific manner and also induce conformational changes in the DNA. Describe the purpose of thses two modes of interaction with the DNA. 2. Draw the structures of the amino acid side chains that correspond to the following histone modification: a) acetylation of lysine; b) phosphorylation of serine; c) phosphorylation of histidine. How do thses modifications change the character of their respective side chain?arrow_forward10. A portion of 5'-AUGCCACGAGUUGAC-3'. What amino acid sequence does this code for? To answer the question please: I) explain what is the genetic code and list the properties of the genetic e 2) draw a diagram of protein synthesis; 3) determine which tRNA should be attached to the mRNA; 4) what is the anticodon for the very first tRNA that will attach to mRNA? mRNA molecule has the sequence anarrow_forward. The genetic code is thought to have evolved to maximize genetic stability by minimizing the effect on protein function of most substitution muta- tions (single-base changes). We will use the six arginine codons to test this idea. Consider all of the substitutions that could affect all of the six arginine codons. (a) How many total mutations are possible? (b) How many of these mutations are "silent," in the sense that the mutant codon is changed to another Arg codon? (c) How many of these mutations are conservative, in the sense that an Arg codon is changed to a functionally similar Lys codon?arrow_forward
- Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning