For 10 points, name this effect causing reduced genetic variation which arises from a colony being settled by a small portion of the original population.
One disease associated with this effect causes dwarfism, polydactyly, and occasional heart abnormalities, Ellis-van Creveld syndrome, and this effect has been blamed for an increased proportion of Huntingon's among Afrikaners. Examples of populations displaying it are the Pennsylvania Dutch and Martha's Vineyard. It often results in a non-random sample of genes and causes results similar to bottlenecking. For 10 points, name this effect causing reduced genetic variation which arises from a colony being settled by a small portion of the original population.
One disease associated with this effect causes dwarfism, polydactyly, and occasional heart abnormalities, Ellis-van Creveld syndrome, and this effect has been blamed for an increased proportion of Huntingon's among Afrikaners.
{Founder Effect} [prompt on Genetic Drift]