Types of Mutations Practice Problems

Which of the following histidine concentrations is expected to have the isolated highest colony growth of mutants that are able to synthesize histidine, in the Ames test using Ethyl Methanesulfonate (EMS)?

Mutations that occur randomly without any external cause are known as "spontaneous mutations." Which of the following is a common type of spontaneous mutation?

What is the purpose of the Ames test?

What is the key difference between transition and transversion mutations?

A type of point mutation that occurs when a purine base is replaced by another purine base or when a pyrimidine base is replaced by another pyrimidine base is termed:

Which of the following options correctly describes the DNA alteration responsible for the Ser-to-Thr missense mutation in the BamHI restriction site of the mutant HAO (homogentisic acid oxidase) gene that causes Alkaptonuria, an autosomal recessive disorder in humans?

The Ames test uses two Salmonella strains, Strain A with a base-substitution mutation and Strain B with a frameshift mutation, and four plates to test the mutagenicity of EMS. Two control plates have no EMS, and two experimental plates have EMS with each strain. What is the significance of the presence or absence of a colony on any of the four plates?  

In a mutagenicity assay, S9 extract is added to Salmonella plates to activate procarcinogens and mutagens. Which of the following best explains why this step is important in the assay?

A microbiologist believes that using proflavin as a test compound in the Ames test using two strains of Salmonella, Strain A (containing base substitution mutation) and Strain B (carrying frameshift mutation) would produce an inaccurate result. The microbiologist's statement is justified because:

Which non-coding RNAs are affected by a mutation in the RNA polymerase III gene?

What diseases have been linked to mutations in the RNA polymerase III gene?

A mutation that changes a codon for leucine to a codon for valine is an example of:

What is a common effect of a mutation in DNA that changes the sequence of mRNA?

Mutations in the gene encoding RNA Pol-I can have a direct effect on:

Which of the following mutations is most likely to result in a truncated protein?

This type of mutation involves the insertion or deletion of one or more nucleotides that shift the reading frame of the gene, resulting in a completely different amino acid sequence downstream of the mutation.

Why are the genomes of small animal models such as D. melanogaster, C. elegans, and zebrafish useful for the study of diseases in humans?

When a single functional allele can provide enough enzyme activity to produce the phenotype, this allele is considered:

Which of the following types of mutation alters the physical and chemical properties of the beta-globin protein, leading to the formation of an abnormal hemoglobin molecule?

Which of the following is a potential limitation of using mouse models to investigate human hereditary disease by producing mutations of the mouse homologs of human genes with precise nucleotide targeting methods? 

If Luria and Delbrück's fluctuation test had supported the adaptive mutation hypothesis, what would the distribution of mutants among cultures have looked like?

What is a feature of DNA replication timing that can contribute to mutational hotspots?

Which protein complex is responsible for detecting and processing  DNA double-strand breaks during the initiation of homologous recombination in eukaryotic cells?

During mismatch repair, what is the role of the MutL protein?

In common cases of cystic fibrosis, phenylalanine 508  is deleted in the CFTR genes. This type of mutation is considered as:

A DNA sequence can be altered in numerous ways.  Consider the following DNA sequences:

Wild type     - 3' ACGCATTGC 5'
Mutant type - 3' ACGTCATTGC 5'

What type of mutation was illustrated in the given sequences?

The impact of mutation in an organism may depend on the type of mutation a specific sequence has undergone. Consider the following mRNA sequence:

3' - UCU - 5' to 3' - CGA - 5'
What type of mutation is illustrated in the given sequence?

Consider the following specific codon in an mRNA sequence:

5' - CAG- 3'

Suppose this codon undergoes a nonsense mutation, which of the following codons can possibly result from this type of mutation?

Point mutation refers to the alteration or change in a single codon in DNA. Consider the following sequence:

5'-CAG-3' to 5'-CAA-3'
What type of point mutation is illustrated in the sequence?

Frameshift mutation can cause a more deleterious impact on an organism. Which of the following can result in a frameshift mutation?

Suppose a wild strain of bacteria cannot grow In a lactose-only medium. If a mutant bacteria which can grow in a lactose-only medium undergoes a reverse type of mutation, what can we expect from the new strain in terms of its growth?

A Drosophila has a white eye color which is a mutant phenotype. After successive breeding with a wild type, the wild phenotype was eventually eliminated from the population. The process in which the mutant phenotype is altered into wild-type is considered as:

In some mutations, a functional gene can be altered into a nonfunctional gene causing a deleterious impact on an organism. The mutation in which the wild-type allele is changed into a detrimental allele is called:

Burkitt lymphoma results from chromosome translocations that involve the Myc gene located in which of the following chromosomes?

Philadelphia chromosome is an example of which of the following types of mutations?

Which of the following statements about mutation is true?

Which of the following statements best explains the distinction between oncogenes and proto-oncogenes?

The APC protein is a tumor suppressor gene that keeps cells from growing and dividing in an uncontrolled way. Mutations in the APC gene are associated with which of the following diseases?

When retinoblastoma is caused by a mutation that occurs in the retinal cells of one eye only, it is called:

An inherited TP53 mutation is known as Li-Fraumeni syndrome. What is the role of the TP53 gene in the body?

Which of the following diseases is associated with a mutation in the protein-coding gene called  MYC Proto-Oncogene?

Fragile X syndrome is the most common inherited cause of intellectual disability and is more common in males than females. Symptoms may include delayed development of speech and language, social anxiety, hyperactivity, attention deficits, and sensory disorders. Fragile X syndrome is caused by a mutation in the _____ on the X chromosome.

All of the following types of mutations are due to errors in DNA replication, EXCEPT:

Mutation in the RB1 gene causes which of the following diseases?

In eukaryotes, many mutations occur in the non-coding regions. When these mutations do not affect gene products or gene expression, they are considered as:

Which one of the following is a disorder that is brought on by mutations in the HEXA gene and is characterized by a lack of the hexosaminidase A enzyme, which is required to break down specific fats in the brain and nervous system?

This is a type of point mutation that happens when a single nucleotide change in the DNA sequence doesn't lead to a change in the amino acid sequence of the protein that is generated.

A mutation that changes the codon AUG to CUG would result in the incorporation of the amino acid:

Which of the following genes provides instructions for making the enzyme phenylalanine hydroxylase, which is involved in the breakdown of the amino acid phenylalanine?

Insulin is a hormone produced by beta cells in the pancreas that regulates the metabolism of carbohydrates, fats, and proteins in the body. The gene for insulin is found on:

PCR amplification can be used to obtain the DNA sequence of the circadian rhythm gene in Drosophila. Which of the following statements is true regarding the cloning of a gene using this technique?

A researcher finds that a string of amino acids at the end of a protein is altered. Which type of mutation is most likely to have occurred in this case?

The sequence of the same portion of a wild-type (WT) protein and its mutant (MUT) form is as follows:
WT:   Met-Val-Leu-Thr-Thr-Trp-Arg 
MUT: Met-Val-Leu-Leu-Leu-Gly-Glu 
Identify the type of mutation in the mutant protein.

Identify the type of mutation in the following figure:

Identify the type of mutation in the following figure:

A point mutation that results in the creation of a premature stop codon in the DNA sequence, resulting in the production of a truncated protein, is termed:

Which of the following types of mutations causes Tay-Sachs disease?

Gaucher disease is a rare genetic disorder that affects the breakdown and storage of certain fatty substances in the body, particularly in the spleen, liver, and bone marrow. It is caused by mutations in the GBA gene, which provides instructions for making an enzyme called glucocerebrosidase. Which of the following options correctly describes the symptoms of Gaucher disease?

Point mutations are changes to a single nucleotide within a DNA sequence. Which of the following is a possible consequence of a point mutation?

The B. anthracis genome is tripartite and comprised of a single circular chromosome and two circular virulence plasmids. The pXO1 plasmid has pagA (protective antigen and an intra membrane toxin transporter), lef (lethal factor, which is a Zn2+-dependent endoprotease), and cyaA (edema factor, which is a calmodulin-sensitive adenylate cyclase). The pXO2 plasmid carries the capsule biosynthesis genes found in a cluster and is essential for full anthrax disease. Which strain is commonly used as a live veterinarian vaccine and which strain was investigated during the anthrax letter attack, respectively?

Haploinsufficiency in genetics describes a model of dominant gene action in diploid organisms, in which a single copy of the wild-type allele at a locus in a heterozygous combination with a variant allele is insufficient to produce the wild-type phenotype. What are the types of inheritance that are a result of gain-of-function mutations (i.e) the disease caused by the change in protein function (as a result of missense mutation) and a result of a mutant form of protein contributing to the formation of dimers or multimers, respectively?

Besides traditional microbiological techniques, a variety of molecular biological methods have been described for the selective identification of B. anthracis. Most of them use specific genes or proteins as targets for recognition and discrimination from related microorganisms. Genomic methods target unique gene sequences located on plasmids or in bacterial chromosomes. The differentiation of B. anthracis from B. cereus sensu stricto, solely based on chromosomal markers, is difficult due to the:

_____________________ result in an amino acid substitution because the codon is changed, and the new codon codes for a different amino acid.

The amino acid sequence of a wildtype peptide is as follows: Met-Cys-Cys-Tyr-Arg-Arg-Val-Thr-Tyr-Thr. The mutant form of the same peptide is as follows: Met-Cys-Cys-Tyr. Identify the type of mutation in the mutant form of the peptide.

In an RNA sequence to be translated (----UACGAAAGCAUA----), a mutation occurred where the mutated sequence led to the termination of protein synthesis after the formation of tyrosine. The mutated sequence is (----UACUAAAGCAUA----). List the reason for the mutated sequence.

Which gene is affected by a point mutation in sickle cell hemoglobin?

Identify the incorrect statement about neutral mutations.

Scientists have discovered approximately 400 different mutations in the HBB gene that cause β-thalassemia. Determine the type of mutation that occurs when the β-polypeptide chain terminates prematurely.

UV light induces mutations in DNA by:

Jacobsen syndrome is a disorder caused by the deletion of a gene from the end of chromosome 11. This type of deletion is referred to as:

The following conditions can be caused by deletion mutations except:

Cri-du-chat syndrome is a genetic condition that is caused by the deletion mutation on:

The most common loss of function mutations are:

Which of the following statements about missense mutation is not true?

Which of the following mutations results in the death of an organism?

The EGFR gene aids in maintaining healthy cell growth and spread. Which of the following is a consequence of the exon 20 insertion mutation in this gene?

A point mutation that changes a nucleotide with another of similar category is called:

Mutations that are caused by insertion generally trigger large-scale changes to the proteins. Which of the following inserted nucleotide numbers have the least adverse impact on the phenotype?

Duchene muscular dystrophy is a condition in which the _______ gene undergoes a nonsense mutation.

Which of the following causes frameshift mutation?

Which of the following mutations has no observable effect on the organism?

Identify the correct statement about somatic cell mutation.

Identify the incorrect statement about mutations.

Identify the type of mutation in the following example:
CAA (glutamine) → CCA (proline)

Marfan syndrome is a genetic disorder that affects the connective tissue. People with this condition are tall and thin and have long arms, legs, fingers, and toes. This disorder is caused by a genetic mutation in which the tyrosine at position 2113 of fibrillin-1 gene is changed into STOP codon. This type of mutation is considered as:

From which of the following sources can we get ionizing radiation?

Which of the following mutations causes sickle cell anemia?

Which of the following point mutations results in a codon that codes for a different amino acid?

 How many nucleotides are affected by a point mutation?

Which of the following statements about ionizing radiation is true?

If a bacteria has 10⁵ bases/genome, what is the rate of mutations/genome replication considering that the bacteria have a mutation rate of 10^-10 mutations/base x replication?