Who speaks for the dead?

WOULD you choose to have a part of your body live on after you died? How might your choice affect your relatives — or even your entire community?

- VICTORIA GIBBON, JESSICA C THOMPSON and SIANNE ALVES

The first is a question people face when they donate organs. The second comes up when they participate in genetic research. This is because DNA from even a single individual can reveal a web of relationships, even helping law enforcement to solve crimes committed by distant relatives they have never met. And as you continue to go back in time, the web becomes ever more tangled.

DNA is the unique genetic material of every living being on the planet. It can be “immortalised” for an unforeseeably long time in digital genetic libraries which contain the genomic information not only of that person, but also of their ancestors and descendants.

Ancient DNA (referred to as aDNA) involves the study of genetic material from organisms that lived long ago, including humans. Geneticists, archaeologists, anthropologists and historians are using aDNA research to gain unprecedented insights into human history, but the knowledge benefits different groups of people unevenly.

Also, it can be destructive because aDNA is normally extracted from small samples of bones or teeth. And who can give permission on behalf of people who lived many generations in the past? Once spoken for, what measures can be used to ensure their wishes continue to be honoured?

Africa is the ancient origin of all humans, as evidenced by having the highest human genetic diversity of any continent or region found today. In other words, all humans carry DNA from deeply rooted shared African ancestry. This makes African DNA (ancient and modern) a rich resource to draw on to understand what makes us human. However, understanding human variation and our origins involves research embedded within living communities and communities are the solution to conservation and the future of work in our disciplines.