Mutations and DNA Repair

These flashcards cover key vocabulary related to mutations and DNA repair mechanisms.

Mutation

A change in the DNA sequence that can lead to variation in a gene.

Somatic Mutation

A mutation that occurs in non-germline (somatic) cells and cannot be inherited.

Germ-line Mutation

A mutation that occurs in the reproductive cells, which can be passed to offspring.

Missense Mutation

A type of mutation that results in a different amino acid being inserted into a protein.

Nonsense Mutation

A mutation that introduces a premature stop codon in the amino acid sequence, truncating the protein.

Frameshift Mutation

A mutation caused by insertions or deletions that alters the reading frame of the gene.

Silent Mutation

A mutation that does not change the amino acid sequence due to redundancy in the genetic code.

Transversion

A type of point mutation where a purine is replaced by a pyrimidine or vice versa.

Insertion Mutation

A mutation in which one or more base pairs are added to the DNA sequence.

Deletion Mutation

A mutation in which one or more base pairs are removed from the DNA sequence.

DNA Repair

The collection of processes by which a cell identifies and corrects damage to its DNA.

Mismatch Repair

A repair mechanism that corrects errors made during DNA replication.

Nucleotide Excision Repair

A DNA repair mechanism that removes and replaces damaged or incorrect segments of DNA.

Base Excision Repair

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

Photoreactivation Repair

A direct DNA repair process that reverses the effects of UV damage to DNA.

Xeroderma Pigmentosum

A genetic disorder characterized by extreme sensitivity to UV light, due to defects in nucleotide excision repair.

De Novo Mutation

A mutation that is newly arisen and not inherited from a parent.

Chemical Mutagen

A chemical agent that can induce mutations in DNA.

Spontaneous Mutation

A mutation that occurs naturally without the influence of external agents.

Phenotypic Effects of Mutations

The way mutations can affect the observable traits of an organism, including neutral, loss-of-function, gain-of-function, and lethal mutations.

Mutagen

An agent that increases the frequency of mutations.

Genetic Variation

Differences in the genetic makeup of individuals, often resulting from mutations.