Gene Mutations and DNA Repair

Flashcards covering key terms and definitions related to gene mutations and DNA repair.

Mutation

A heritable change in genetic information.

Induced Mutation

A mutation caused by environmental factors such as chemical mutagens or UV radiation.

Spontaneous Mutation

A mutation that occurs naturally due to errors in replication or crossing over.

Base Substitution Mutation

A mutation involving a change in a single nucleotide of DNA.

Frameshift Mutation

A mutation caused by the insertion or deletion of nucleotides that disrupts the reading frame.

Missense Mutation

A base substitution that results in a different amino acid being encoded.

Nonsense Mutation

A base substitution that creates a stop codon, leading to premature termination of translation.

Silent Mutation

A base substitution that does not change the amino acid sequence due to codon redundancy.

Loss of Function Mutation

Results in complete or partial absence of protein function.

Gain of Function Mutation

Results in an abnormal protein function, including new functions or overproduction.

Mismatched Repair

A DNA repair mechanism that fixes mismatched nucleotides after DNA replication.

Base-Excision Repair

A repair process that removes and replaces damaged bases in DNA.

Nucleotide-Excision Repair

Removes and replaces damaged DNA that distorts the DNA structure.

Transversion Mutation

A mutation where a purine is substituted with a pyrimidine or vice versa.

Transition Mutation

A mutation where a purine is substituted with a different purine or a pyrimidine with a different pyrimidine.

Chemical Mutagen

An agent that increases the rate of mutation by chemically damaging DNA.

Deamination

The loss of an amino group from a base, altering its pairing properties.

Depurination

The breaking of the bond linking a purine base to its deoxyribose sugar, creating an apurinic site.