Haplotype evolution and linkage disequilibrium: A simulation study.

We simulated the evolution of a three-site haplotype system, two restriction fragment length polymorphisms flanking one short tandem repeat polymorphism, under five different demographic scenarios, three with constant population size and two with population growth. The simulation was designed to observe the effects of population history, recombination fraction, and mutation rate on allele and haplotype frequencies, haplotype diversity, frequency of ancestral alleles, and linkage disequilibrium. The known ancestral haplotypes were often found at low frequencies and even became extinct after 5, 000 generations, especially with small effective population sizes. The original linkage disequilibrium was eroded and even reversed. Copyright 2000 S. Karger AG, Basel.