founderhatás

The founder effect is a concept in population genetics that describes the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. This small sample of individuals may not be representative of the original population's genetic diversity. Consequently, the new population will have a genetic makeup that reflects the gene pool of the founders, which may differ significantly from the original population. This can lead to certain alleles, both common and rare, being present at higher or lower frequencies than in the source population, or even being absent altogether.

The founder effect is a specific instance of genetic drift, which is the random fluctuation of allele frequencies in a population due to chance events. In the case of the founder effect, the "chance event" is the random sampling of individuals that establish the new population. This phenomenon can have significant implications for the genetic characteristics of isolated or newly formed populations. For example, if a rare genetic disease allele is present in the founder individuals, it can become much more common in the descendant population, even if it was very rare in the original population. This effect is particularly pronounced in species with limited dispersal capabilities or in situations where a small group migrates to a new habitat.