DISPERSION OF HUMAN Y-CHROMOSOME HAPLOTYPES BASED ON 5 MICROSATELLITES IN GLOBAL POPULATIONS

We have analyzed five microsatellite loci from the nonrecombining port ion of the human Y chromosome in 15 diverse human populations to evalu ate their usefulness in the reconstruction of human evolution and earl y male migrations. The results show that, in general, most populations have the same set of the most frequent alleles at these loci. Hypothe tical ancestral haplotypes, reconstructed on the basis of these allele s and their close derivatives, are shared by multiple populations acro ss racial and geographical boundaries. A network of the observed haplo types is characterized by a lack of clustering of geographically proxi mal populations. In spite of this, few distinct clusters of closely re lated populations emerged in the network, which are associated with po pulation-specific alleles. A tree based on allele frequencies also sho ws similar results. Lack of haplotypic structure associated with the p resumed ancestral haplotypes consisting of individuals from almost all populations indicate a recent common ancestry and/or extensive male m igration during human evolutionary history. The convergent nature of m icrosatellite mutation confounds population relationships. Optimum res olution of Y chromosome evolution will require the use of additional m icrosatellite loci and diallelic genetic markers with lower mutation r ates.