Estimating population structure in diploids with multilocus dominant DNA markers.
Multilocus DNA markers [random amplified polymorphic DNA (RAPDs), amplified fragment length polymorphism (AFLPs)] are important for population studies because they reveal many polymorphic loci distributed over the genome. The markers are dominant, that is two phenotypes are distinguished at each locus, with a band and with no band. The latter one represents null-homozygotes with unamplified, recessive null-alleles. The frequency of a null-allele can be estimated by taking the square root of the fraction of individuals with no band. Lynch and Milligan (1994) have suggested a modified procedure that reduces bias introduced by the square-root transform. However, the procedure recommends to ignore those samples in which fewer than four null-homozygotes are observed. This may lead to significant bias in estimates of genetic diversity. In this study, I introduce a Bayesian approach to estimation of null-allele frequencies for dominant DNA markers. It follows from computer simulations and data on two conifer species that the Bayesian method gives nearly unbiased estimates of heterozygosity, genetic distances and F-statistics. The influence of a prior distribution and departure from Hardy-Weinberg proportions on the estimates is also considered.
Zhivotovsky
L A
LA
N.I. Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia. lev@vigg.ru
D000483:Alleles; D001499:Bayes Theorem; D003198:Computer Simulation; D018744:DNA, Plant / Q000032:analysis; D004171:Diploidy; D005787:Gene Frequency; D005799:Genes, Dominant; D005808:Genes, Recessive; D005819:Genetic Markers; D014644:Genetic Variation; D019105:Random Amplified Polymorphic DNA Technique; D014197:Trees / Q000235:genetics*
D018744:DNA, Plant; D005819:Genetic Markers