Carriers of human mitochondrial DNA macrohaplogroup M colonized India from southeastern Asia

ABSTRACT Objetives We suggest that the phylogeny and phylogeography of mtDNA macrohaplogroup M in Eurasia and Australasia is better explained supposing an out of Africa of modern humans following a northern route across the Levant than the most prevalent southern coastal route across Arabia and India proposed by others. Methods A total 206 Saudi samples belonging to macrohaplogroup M have been analyzed. In addition, 4107 published complete or nearly complete Eurasian and Australasian mtDNA genomes ascribed to the same macrohaplogroup have been included in a global phylogeographic analysis. Results Macrohaplogroup M has only historical implantation in West Eurasia including the Arabian Peninsula. Founder ages of M lineages in India are significantly younger than those in East Asia, Southeast Asia and Near Oceania. These results point to a colonization of the Indian subcontinent by modern humans carrying M lineages from the east instead the west side. Conclusions The existence of a northern route previously advanced by the phylogeography of mtDNA macrohaplogroup N is confirmed here by that of macrohaplogroup M. Taking this genetic evidence and those reported by other disciplines we have constructed a new and more conciliatory model to explain the history of modern humans out of Africa.