The lineage-based approach-which involved phylogeographic analysis of uniparental non-recombining DNA, based on regionally specific, highly detailed, reconstructed gene trees-has illuminated detailed geography of migrations-in particular, the exit route of AMH from Africa. This population-based approach had problems of resolution and dating, but results were largely consistent with an African ancestry for anatomically modern humans (AMH). Genetic relationships between human groups were first studied by comparisons of relative allele frequencies at multiple loci. NRY with a lower SNP mutation rate still has a dating problem relating to use the of single tandem repeats (STRs), but has validated mtDNA results and with more geographical specificity and genomic size, as with the autosomal human genome, has much more detail to offer for the future. The worldwide skeleton phylogeny of mtDNA is fully resolved, but a regional analysis will continue to illuminate subsequent migrations. AMH left Africa via a single southern exit about 70 000 years ago and rapidly spread around the Indian Ocean towards the Antipodes, long before a small branch left a South Asian colony, earlier on the trail, to populate Europe. mtDNA, with its high single nucleotide polymorphism (SNP) mutation rates and relative ease of dating, led the way and gave stronger proof of the recent near replacement of all human species by anatomically modern humans (AMH). Geographical study of detailed, highly resolved trees of single, non-recombining uniparental loci (mitochondrial DNA: mtDNA and Y chromosome/non-recombining Y: NRY), following specific lineages rather than populations, then revolutionized knowledge of the peopling of the world, although, curiously, the use of geographically highly specific mutations that protect against malaria, found on individual autosomal globin genes, were first in single-locus phylogeography. Genetic relationships between human groups were first studied by comparisons of relative allele frequency at multiple loci.
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