June 29, 2007 “People are trapped in history, and history is trapped in them”*. James Baldwin’s well-known quotation aptly captures the essence of The Genographic Project – an ambitious five-year expedition through our genetic past that aims to understand where humans came from and how we got to where we are today. Eighteen months into the project, the first findings outlining the procedures used to analyze the genetic data from 78,590 public participants have been released. In the report published in the open-access journal PLoS Genetics, Doron Behar and colleagues also give the first anthropological insights into the emerging genetic map of human history.
The Genographic Project was launched by the National Geographic Society, IBM, geneticist Spencer Wells and the Waitt Family Foundation in 2005 with the aim of answering questions about the distribution and diversity of the human race that can’t be answered by studying the fossil record. Although we can pinpoint the origin of Homo sapiens to Africa 60,000 years ago, little is known about the exact nature of the human diaspora that led us to the present day, and this is where genetics (in particular the study of mitochondrial DNA (mtDNA) in which there is usually no change from parent to offspring) can provide the answers.
Having established ten research laboratories around the globe, the Project now boasts the largest standardized human mitochondrial DNA database ever with 78,590 genotypes collected from public participants. An open-source research database has been created from this study from which a map of ancient human migrations is being created for the first time. The collection of samples is ongoing and urgent, as mixing populations obscure the genetic signals that distinguish different populations, making the task of tracing them backward to their common African root more difficult as time goes by.
Acquiring genetic samples from the world's remaining indigenous and traditional peoples is critical to achieving this goal and although everyone is encouraged to participate, emphasis is being placed on collecting samples from remote regions where the ethnic and genetic identities of populations remain isolated.
The new report from Doron Behar and colleagues describes the procedures used to generate, manage, and analyze the genetic data and provides insight into the structure of the mtDNA tree including more accurate methods of classifying distinct mitochondrial genetic lineages called haplogroups. These methodologies and data sets are being made publicly available and will be updated periodically as the Project progresses. Interestingly, the report also discusses the search for evidence mtDNA from Neanderthal and other ancient human species – but the results do not support the existence of these samples in the database.
A map of our past
As part of the Genographic Project a fascinating online map has been created that charts the history of human migration over the last 60,000 years. The map provides insight into the various migration routes spanning out from Africa to reach remote corners of the globe such as to South America and Australia where humans arrived around 50,000 years ago.
Further participants are needed for the ongoing project. A participation kit (costing $99) is available here. The kit enables the submission of DNA via a simple cheek swab.
* James Baldwin - Notes of a Native Son