New statistical method reveals surprises about our ancestry

A statistical approach to studying genetic variation promises to shed new light on the history of human migration. Scientists from the University of Oxford and University College Cork have developed a technique that analyses shared parts of chromosomes across the entire human genome. It can give much finer detail than other methods and makes it possible to delve further back in time and identify smaller genetic contributions. Application of the method has already turned up such surprising findings as a strong Mongolian contribution to the genes of the Native American Pima people and gene flow from the north of Europe to Eastern Siberia. Details are published May 23rd in the open-access journal PLoS Genetics.

Previous methods of genome analysis have either concentrated on one part of the human genome – for example, just the Y-chromosome -- or are based on "beanbag genetics" – an oversimplified model of heredity that does not fully consider chromosomal structure. The new technique described by Hellenthal and colleagues was used to analyse 2000 genetic markers using Single Nucleotide Polymorphism data from the 2006 Human Diversity Project. The researchers believe their method can cope with much larger datasets with over 500,000 genetic markers.

Further developments of the technique should allow more finely detailed reconstruction of human ancestry and give a perspective independent of anthropological theory and interpretation.

Source: Public Library of Science