Practice question

Founder effect occurs when small number of individuals colonize new territory, establishing population whose allele frequencies reflect by chance composition of founders, not source population frequencies. This random sampling mirrors genetic drift mechanism, where allele frequencies shift due to finite gamete sampling rather than natural selection. If founders happen to carry rare allele at elevated frequency, new population shows unusually high prevalence of that allele. Thus founder effect represents special case of drift induced by sampling during colonization, often cited for rare diseases in isolated communities like Ashkenazi or Finnish populations.