Researchers of the Human Genographic Project have confirmed that the ancestors of modern humans in Europe, Asia and Oceania originally left Africa through Arabia. The confirmation comes after a six-year effort to map the genetic pattern of humans. Prior to the study, it was believed that the ancestors of modern day humans crossed through a northern route through Egypt. The study suggests that South Asia played a key role in populating the globe. The study was published in the journal ‘Molecular Biology and Evolution.' Non-African descendants are believed to have migrated out of Africa roughly 70,000 years ago. Researchers found that the Indian populations had more genetic diversity than Europeans and East Asians, which gives a good indicator of the age of a population. The Indian statistics seem to support the theory of migration southwards along coastal routes as they continued through East Asia into Oceania. Researchers say that a route through the Arabian Peninsula explains the genetic diversity patterns much better than a route through Egypt's Sinai desert. Stretching their conclusions further, researchers say this also supports the idea that sea levels might have been low enough for humans to cross from the horn of Africa into Arabia via the Bab-el-Mandeb straits in the Red Sea. The research was based on a new analytical method which exploits patterns of recombination in human genomes. Recombination is the process by which DNA molecules are broken up and recombined to form new pairs. By analyzing the recombination patterns, researchers trace relationships between different present-day humans “Almost 99% of the genetic makeup of an individual are layers of genetic imprints of the individual's many lineages,” said IBM researcher Laxmi Parida. “Our challenge was whether it was even feasible to tease apart these lineages to understand the commonalities,” “Through a determined approach of analytics and mathematical modelling, we undertook the intricate task of reconstructing the genetic history of a population. In doing so, we now have the tools to explore much more of the human genome.” According to the director of the Genographic Project, such methods could give researchers “greater insights into the migratory history of our species”. Almost half a million people had participated in the Genographic Project, making it one of the biggest human genetic variation surveys ever attempted. BM
