DNA-SEQUENCES OF ALU ELEMENTS INDICATE A RECENT REPLACEMENT OF THE HUMAN AUTOSOMAL GENETIC COMPLEMENT

DNA sequences of neutral nuclear autosomal loci, compared across diver se human populations, provide a previously untapped perspective into t he mode and tempo of the emergence of modern humans and a critical com parison with published clonally inherited mitochondrial DNA and Y chro mosome measurements of human diversity. We obtained over 55 kilobases of sequence from three autosomal loci encompassing Aln repeats for rep resentatives of diverse human populations as well as orthologous seque nces for other hominoid species at one of these loci. Nucleotide diver sity was exceedingly low. Most individuals and populations were identi cal. Only a single nucleotide difference distinguished presumed ancest ral alleles from descendants. These results differ from those expected if alleles from divergent archaic populations were maintained through multiregional continuity, The observed virtual lack of sequence polym orphism is the signature of a recent single origin for modern humans, with general replacement of archaic populations.