1.6 mutations

Mutation

A permanent change to the actual sequence of DNA bases that can lead to the alteration or absence of proteins.

Point Mutation

A mutation that occurs in the genetic code of human cells through an error in DNA replication, often affecting non-coding DNA.

Base Substitution

A type of point mutation where one nucleotide with a base is substituted for a different nucleotide.

Silent Mutation

A mutation that occurs when a base substitution results in a codon that corresponds to the same amino acid.

Missense Mutation

A mutation that occurs when a base substitution results in a codon coding for a different amino acid.

Nonsense Mutation

A mutation that occurs when a base substitution results in a codon that codes for a stop codon instead of an amino acid.

Large Scale Mutations

Mutations involving large-scale changes to the structure or number of chromosomes in a cell, typically occurring during meiosis.

Deletion

A type of large scale mutation where genetic material breaks off from a chromosome and is lost.

Duplication

A large scale mutation involving the presence of extra copies of genes on chromosomes.

Translocation

A mutation where a section of one chromosome detaches and moves to a new chromosome.

Inversion

A large-scale mutation where a section of a broken chromosome is inserted back in reversed order.

Insertion

A type of mutation where a section of DNA from one chromosome is removed and added to another chromosome.

Aneuploidy

A chromosome mutation that leads to an abnormal number of chromosomes.

Mutagens

Factors that increase the rate of mutation, which can be physical, chemical, or biological in nature.

Consequences of Mutations

Germline mutations can be passed on to future generations, while somatic cell mutations can cause serious diseases but are not inherited.

physical mutagens

high energy radiation

chemical mutagens

chemicals in the environment such as asbestos or cigarette smoke

biological mutagens

viruses