Polymorphisms

Genetic polymorphisms are different forms of a DNA sequence. "Poly" means many, and "morph" means form. Polymorphisms are a type of genetic diversity within a population's gene pool. They can be used to map (locate) genes such as those causing a disease, and they can help match two samples of DNA to determine if they come from the same source. Depending on its exact nature, a polymorphism may or may not affect biological function.

A short tandem repeat (STR) polymorphism at a particular locus on a chromosome.