- For the guitarist named Gene Pool, see Greg Flesch.
In population genetics, a gene pool is the complete set of unique alleles in a species or population. A large gene pool indicates extensive genetic diversity, which is associated with robust populations that can survive bouts of intense selection. Meanwhile, low genetic diversity (see inbreeding and population bottlenecks) can cause reduced biological fitness and an increased chance of extinction.
When many alleles exist for a given gene or locus, a population is said to be polymorphic with respect to that gene or locus. When no variation exists, it is labelled monomorphic.