founder effect


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found·er ef·fect

an unusually high frequency of a gene in a particular population derived from a small set of unrepresentative ancestors.

founder effect

n.
A random difference in allele frequencies of a population founded by a small group of organisms relative to the allele frequencies in the original population.

founder effect

the result of starting a new population with a low number of individuals (founders), so that their GENE POOL may not contain the same proportions of ALLELES for a particular LOCUS as in the original population. For example, instead of containing three alleles of the ABO BLOOD GROUP locus, Australian aborigines contain no B alleles and thus no Group B or Group AB individuals are produced, a situation probably caused by a ‘founder effect’. Such small founder populations are subject to RANDOM GENETIC DRIFT.

founder effect

extreme genetic drift that occurs when a new population is based on only a few individuals ('founders'). Called also founder principle.
References in periodicals archive ?
Family described here also belongs to Kashmir (Pakistan), so this recurrent mutation is reflecting the founder effect in Kashmiri (Pakistan) consanguineous families affected by pycnodysostosis.
Of the six people that had the mutation, five instances could be traced to founder effects, and one case could be traced to a marriage between close relatives.
The variability of the current population is the result of the contribution of few ancestors, who are mostly also founders, evidencing that the population was developed from a narrow genetic base that characterizes the occurrence of founder effects.
Clinical patterns of human Y chromosomal diversity in continental Italy and Greece are dominated by drift and founder effects.
High prevalence of e novel mutation (2268 insT) of the thyroid peroxidase gene in Taiwanese patients with total iodide organification defect and evidence for a founder effect.
For example, the only disease --so far studied-- in Costa Rica showing a clear founder effect is Wilson's disease.
A mutation in one of the genes linked to hereditary nonpolyposis colorectal cancer probably was established through a founder effect unique to the United States and may account for a significant percentage of such cancers in the white U.
Another phenomena, the bottleneck effect is related to the founder effect and occurs when only a small portion of the original population survives to serve as the sole source of the population.
The great majority of affected alleles carry an A985G transition (causing Lys329Glu substitution), which seems to have been propagated by a founder effect [6].