Quick. Where's your genome from? Sounds like an easy enough question, and most of us wouldn't hesitate before answering. England, Scotland, Spain, Senegal, China. But do we really know?
This is the premise behind the National Geographic Society's recently launched Genographic Project, which aims to amass the world's largest collection of DNA samples in order to map how human migration led to the population of the planet.
As a genome scientist interested in the evolutionary and migratory history of my species, it's hard not to get excited by the prospect of the Genographic Project and what it might tell us about our genomes and ourselves. Part of the appeal is the scale of the project. For population studies of any kind, bigger is almost always better: the more data one can analyze, the more likely one's conclusions are valid. The thought of collecting a hundred thousand or more genomic snapshots from the remotest corners of the globe to reconstruct human population history is a tantalizing one that fits well with some of the aims of the IGSP, especially our Center for Population Genomics and Pharmacogenetics."The thought of collecting a hundred thousand or more genomic snapshots from the remotest corners of the globe to reconstruct human population history is a tantalizing one ..."
However, there are at least two concerns about the Genographic Project. The first is the question of fair access. In the early 1990s, an initiative known as the Human Genome Diversity Project ran into trouble when it set out to sample a variety of indigenous populations for clinical and evolutionary research purposes and failed to make its case to many of those populations it wished to study. The result: the HGDP was delayed for about 10 years.
The Genographic organizers – some of whom were integrally involved in the HGDP – say they've learned their lesson. They say they will continue to seek advice and counsel from indigenous leaders as they proceed. They say their project will not involve medical research of any kind and will therefore be free from disputes over commercialization. They say they will give back to the communities they study through educational activities and cultural preservation projects. But it is notable that the National Geographic Society's press announcement was followed closely by one from a group called the Indigenous Peoples Council on Biocolonialism that sharply opposed the Genographic Project as an "unwanted intrusion" and just another form of biopiracy.
Not only is the Genographic Project turning a blind eye to the medical implications of its work, it seems also to be ignoring the other elephant in the room: race. You've read about the issues in these pages before: is race nothing but a social construct or does it have a biological basis? Can populations be distinguished on the basis of race? Should race be considered when prescribing medications? These issues are central to many of us within the IGSP. Not so the Genographic Project: "There is no desire to look at race," according to one of the project leaders. For its part, the project will only tell participants what migratory routes their ancestors took and which "branch" of the human family tree they belong to.
Genomes gather traces of their travels through history and have stories to tell, whether we want to hear them or not. In many populations, admixture between genomes is increasingly evident, whether reflecting the African diaspora, wars and invasions by hostile nations, or simply chosen relationships between peoples of different ethnic or racial origins. The concept of mixed genomes may cause confusion and much angst among participants. What will it mean to be told that 20 percent of your genome comes from a different origin than you expected? That'll make for some interesting discussions around the dinner table or around the classroom…
Is our current understanding of genetic diversity up to the task? Perhaps, but perhaps not. Our knowledge of the relative minority of genome variants that are specific for certain geographic origins is incomplete at the moment, based largely on studies of a limited number of "parent" populations – western European, west African, east Asian and indigenous American. The public may not settle for a vague answer, not when the Genographic Project is charging $100 to participate.
There is evidently much more to learn about genome variation, both shared among and private to particular population groups. One hopes that the Genographic Project, like other large-scale studies of different populations, will contribute to that knowledge and provide useful databases for study of human history and human health. The story of human migration and the circuitous paths our genomes have taken can't help but be a fascinating one. Here's hoping it can be told in ways that are inclusive, equitable and enlightening to all.
Huntington F. Willard