Mutations

Point mutations

A single change in a nucleotide

Base substitutions

A type of point mutation where a amino acid is switched out for another

Silent mutations

A mutation that causes no change in the resulting amino acid

Missense mutations

A point mutation that changes a single amino acid

Nonsense mutations

A point mutation that makes changes to a stop codon

Frameshift mutations

A mutation where a base is added or removed and shifts the entire nucleotide sequence off by one

Splice site mutations

A mutation that alters the ability for mRNA to be properly modified

Promoter mutations

Can increase or decrease the speed of transcription

Somatic cell mutations

A mutation that occurs during embryo development. Only a small portion of the organism is affected

Germ-line mutations

A mutation that occurs before conception. The entire organism carries the mutation.

Spontaneous mutations

Mutations such as Errors in DNA replication, changes in nucleotide structure and Toxic metabolic processes.

Induced mutations

Mutations that occur from chemical and physical agents.

Chemical agents

Things such as cigarettes

Physical agents

Things such as UV radiation

Errors in DNA replication

A point mutation caused by DNA polymerase

Toxic metabolic products

When something involved in normal metabolism reacts and damages DNA

Changes in nucleotide structure

When a purine and a deoxyribose just spontaneously break