Ai. Pudovkin et al., ON THE POTENTIAL FOR ESTIMATING THE EFFECTIVE NUMBER OF BREEDERS FROMHETEROZYGOTE-EXCESS IN PROGENY, Genetics, 144(1), 1996, pp. 383-387
The important parameter of effective population size is rarely estimab
le directly from demographic data. Indirect estimates of effective pop
ulation size may be made from genetic data such as temporal variation
of allelic frequencies or linkage disequilibrium in cohorts. We sugges
t here that an indirect estimate of the effective number of breeders m
ight be based on the excess of heterozygosity expected in a cohort of
progeny produced by a limited number of males and females. In computer
simulations, heterozygote excesses for 30 unlinked loci having variou
s numbers of alleles and allele-frequency profiles were obtained for c
ohorts produced by samples of breeders drawn from an age-structured po
pulation and having known variance in reproductive success and effecti
ve number. The 95% confidence limits around the estimate contained the
true effective population size in 70 of 72 trials and the Spearman ra
nk correlation of estimated and actual values was 0.991. An estimate b
ased on heterozygote excess might have certain advantages over the pre
vious estimates, requiring only single-locus and single-cohort data, b
ut the sampling error among individuals and the effect of departures f
rom random union of gametes still need to be explored.