Last night I went to hear Dr Spencer Wells speak at Benaroya Hall. He is the leading geneticist and director of The National Geographic Genographic Project. If you have not yet heard of his project, it is quite fascinating. By collecting DNA samples from every corner of the Earth, he is creating a very detailed family tree that reveals how every one of us is related. His data has shown that we were all related to each other through a common ancestor only 2000 generations ago. Last night, he gave an update on the data that he and his colleagues have collected so far over the past 2 years. One important theme he stressed was how the migration pattern of DNA responded to climatic change. He showed several slides of how the earth appeared over the past 50,000 years, showing how the African deserts as well as Asian coast lines were significantly affected by the 20,000 yr cycle of the Earth’s axial shift. He also showed how this time line corresponded to the time when our human ancestral “Adam” and “Eve” first migrated out of Africa. Another interesting story was how a Hungarian woman who participated by supplying her DNA, complained that her lineage analysis must have been incorrect because it showed that she was from Asia. That led him to further analyze all the Hungarians in the data pool which confirmed the early Asian origins of at least 5% of the Hungarian population.
Although analysis is currently limited to only the Y and mitochondrial DNA, perhaps migration patters will be sufficient to help explain some of the interesting patterns of disease incidence found in some populations but not others. For example, the Inuit Eskimos and ethnic Chinese share a high incidence of angle closure glaucoma, where as the Japanese population does not. An early separation of the Japanese population from the ethnic Chinese might explain this. This information might help clinicians to better asses risk for diseases that might be more common in certain populations but that we do not have a specific genetic test for yet. Especially for patients who are Hapa or of mixed ancestry, this type of individualized ethnic background data could help patients at least receive more optimized preventative medicine.