Some comments on the variance of heterozygosity in finite populations

A new and more accurate formula for the variance of heterozygosity under genetic drift has been obtained. The variance can be partitioned into two components; the first comes from the dispersion of the allelic frequencies among populations, and the second from the dispersion of the actual heterozygosity, h, around their expected values, 2pq. A certain generation exists where the variance reaches a maximum; thus, the genetic drift can be split into two phases by this single maximum.