Gene Mutations

Question 1

Point Mutations

Answer 1

Alterations of a single or a few base pairs.

Question 2

Silent mutations

Answer 2

A change that does not affect the amino acid sequence.

Question 3

Conservative Substituitions

Answer 3

Mutations that may change the amino acid sequence, but the replacement and the original amino acid have similar biochemical properties, and the change will not drastically affect protein function.

Question 4

Non-conservative Substituitions

Answer 4

Mutations that result in the replacement of an amino acid with a biochemically different amino acid, which changes the biochemical nature of the protein.

Question 5

Nonsense Substituitions

Answer 5

Mutations that terminate proteins prematurely when a nucleotide substitution produces a stop codon instead an amino acid codon.

Question 6

Antigen Retreival

Answer 6

Treatment that can uncover antigen epitopes. It allows an antibody to access the target protein within the tissue. Enzyme digestion with protein-digesting enzymes or heating tissue sections in water or buffer.

Question 7

Cryostat

Answer 7

An instrument that allows cutting of frozen tissue into 4- to 15-micron sections inside a chamber held at -20C.

Question 8

HPLC

Answer 8

High Performance Liquid Chromatography. The basis for separation and analysis instruments such as amino acid analyzers.

Question 9

Isocratic

Answer 9

Organic solvent in the mobile phase in chromatography that may be the same throughout the column.

Question 10

SSCP

Answer 10

Single-Strand Conformation Polymorphism. Hybridization based method. A method designed to detect sequence alterations in DNA through differences in secondary structure due to differences in the nucleotide sequence.

Question 11

Conformer

Answer 11

A three dimensional structure formed by folding and intrastrand hybridization of a single strand of nucleic acid.

Question 12

Melt Curve Analysis

Answer 12

MCA. Post-amplification step of RT-PCR. Mutation or polymorphism scanning based on changes in hybridization temperature.

Question 13

Homoduplexes

Answer 13

dsDNA in which the component strands are completely complementary.

Question 14

Heteroduplex Analysis

Answer 14

HDA. Detection of sequence differences by denaturation and renaturation of test and reference ds nucleic acids, forming heteroduplexes where test sequences differ from reference sequences.

Question 15

Standard Tiling

Answer 15

Design of probes on an array such that the mutation site is always in the same position from the end of the probe.

Question 16

Redundant Tiling

Answer 16

Design of probes on an array such that a predictable mutation is located at different places in the probe sequence.

Question 17

Bead Array

Answer 17

Probes attached to a fluorescence-labeled beads.

Question 18

SSP-PCR

Answer 18

Sequence-specific (primer) PCR. Detects point mutations and other SNPs in DNA with primers designed so that the 3’ -most base of the primer hybridizes to the test nucleotide position in the template.

Question 19

NIRCA

Answer 19

Nonisotopic RNase cleavage assay. Heteroduplex analysis using duplex RNA. A mutation or polymorphism screening and amplification method using RNase cleavage of heteroduplexes.