wildtype

Wild type is a term used in genetics to describe the phenotype or genotype that is most commonly observed in nature or in a given population. It serves as a reference point for comparing variants that arise through mutation, breeding, or genetic engineering. The designation implies the form that is typical under ordinary environmental conditions, rather than an ideal or superior state.

In practice, a wild-type allele is the non-mutant version at a locus that is most representative of the population. However, wild type is a relative concept: what is considered wild type can vary with environment, population, and evolutionary history. Different ecological or geographic contexts can give rise to multiple common or locally prevalent forms, so there can be several wild-type phenotypes across ecotypes or species.

In laboratory genetics, wild type often refers to the standard, non-mutated background against which experimental mutations are measured. Model organisms used in research typically have well-established wild-type strains that are used as baselines, though these laboratory strains may be adapted to controlled conditions and differ from wild populations in meaningful ways.

The term does not imply that the wild type is the most fit in all environments, nor that it is the single or ultimate normal. Evolution by natural selection, drift, migration, and environmental change can shift which traits are typical, and what is considered wild type in one context may differ in another.

See also allele, mutation, genotype, phenotype, population genetics.