Molecular Quiz 8

A reference segment of DNA has the following sequence: GCTCACCATGG. The fourth nucleotide is changed to an A in a particular genetic disease. How would this mutation be denoted by accepted nomenclature? a. 4C>A b. 8A>C c. 4delC d. 8insA

a. 4C>A

Which of the following mutations is more likely to result in a phenotypic change? a. Frameshift mutation at the beginning of the coding sequence b. Silent mutation in the middle of the coding sequence c. Nonconservative mutation at the end of the coding sequence d. Conservative mutation at the end of the coding sequence

a. Frameshift mutation at the beginning of the coding sequence

Which of the following laboratory methods used to detect mutations relies on sequence-specific dissociation of double-stranded DNA? a. Melt-curve analysis b. Denaturing gradient gel electrophoresis c. Allele-specific oligomer hybridization d. HPLC

a. Melt-curve analysis

A patient with a family history of breast cancer, in which several affected relatives have a known mutation in the BRCA1 gene, is screened for the presence of the mutation by allele-specific PCR. Amplification from primers corresponding to the normal sequence was observed. Amplification was also observed with the primers complementary to the mutant sequence. Which of the following corresponds to the correct interpretation of these results? a. The patient has a heterozygous mutation in BRCA1. b. The patient has a homozygous mutation in BRCA1. c. The patient has a normal BRCA1 sequence. d. The results are not valid.

a. The patient has a heterozygous mutation in BRCA1.

What is MALDI-TOF? a. ELISA performed under controlled conditions b. A type of mass spectrometry c. Gel-based electrophoresis d. An HPLC method

b. A type of mass spectrometry

Substitution of leucine with valine in an amino acid sequence is what type of mutation? a. Nonconservative b. Conservative c. Silent d. Nonsense

b. Conservative

Which of the following methods has the highest sensitivity, specificity, and accuracy as far as detecting DNA mutations in clinical applications? a. Single-strand conformation polymorphism b. PCR-RFLP c. High-density oligonucleotide array d. ELISA

b. PCR-RFLP

The codon UGG is mutated to UGA. What will happen to the encoded protein? a. The mutated protein will be more hydrophilic. b. Premature termination will occur. c. There will be no effect. d. The amino acid length will increase.

b. Premature termination will occur.

Which is the source of monoclonal antibodies? a. Mouse plasma b. Mouse stem cells c. Mouse ascites d. Cell lines

d. Cell lines

Which method can detect gene mutations in situ? a. RIA b. EIA c. HPLC d. IHC

d. IHC