Genomic sharing surrounding alleles identical by descent: effects of genetic drift and population growth.

The number of identical deleterious mutations present in a population may become very large, depending on the combined effect of genetic drift, population growth and limited negative selection. The distribution of the length of the shared area between two random chromosomes carrying the mutations has been investigated for a number of generations varying from 20-100 since introduction. The consequences for investigations using association and haplotype sharing methods are discussed.