Changes

: [[Mutation]]s affect [[Gene Expression|gene expression]]. Since [[gene]]s act as templates for building [[protein]], if a [[gene]] has been altered by [[mutation]] the [[protein]]s will also be changed.

: [[Mutation]]s lead to the [[protein]]s, [[Coding DNA|coded]] for by a [[gene]], to have a different shape and function. A [[mutation]] may cause the [[Active Site|active site]] of an [[enzyme]] to change, leading to a [[Substrate (Biology)|substrate]] no longer fitting in the [[Active Site|active site]] or, in rare cases, a different [[Substrate (Biology)|substrate]] fitting the [[Active Site|active site]].