Mutation
Key Stage 4
Meaning
A mutation is a change to the DNA in a cell which causes a new variant of a gene.
About Mutations
- Mutations occur randomly so they cannot be predicted.
- Most mutations are errors which occur during DNA replication in cell division. However, some can occur due to DNA becoming damaged by ionising radiation.
- Mutations affect gene expression. Since genes act as templates for building protein, if a gene has been altered by mutation the proteins will also be changed.
- Mutations lead to the proteins, coded for by a gene, to have a different shape and function. A mutation may cause the active site of an enzyme to change, leading to a substrate no longer fitting in the active site or, in rare cases, a different substrate fitting the active site.