ORIGINS AND AFFINITIES OF MODERN HUMANS - A COMPARISON OF MITOCHONDRIAL AND NUCLEAR GENETIC DATA

To test hypotheses about the origin of modern humans, we analyzed mtDN A sequences, 30 nuclear restriction-site polymorphisms (RSPs), and 30 tetranucleotide short tandem repeat (STR) polymorphisms in 243 African s, Asians, and Europeans. An evolutionary tree based on mtDNA displays deep African branches, indicating greater genetic diversity for Afric an populations. This finding, which is consistent with previous mtDNA analyses, has been interpreted as evidence for an African origin of mo dern humans. Both sets of nuclear polymorphisms, as well as a third se t of trinucleotide polymorphisms, are highly consistent with one anoth er but fail to show deep branches for African populations. These resul ts, which represent the first direct comparison of mtDNA and nuclear g enetic data in major continental populations, undermine the genetic ev idence for an African origin of modern humans.