What is Molecular Anthropology?
It is a recent field of academic work called molecular anthropology. Molecular because information is derived from large molecules such as proteins and the nucleic acids ribonucleic acids or RNA and deoxyribonucleic acids or DNA.
It is Anthropology because we reconstruct the nature of human societies in their pre-literate stages, before industrial life came along. As we are about 150,000 years old and live in industrial society for at most 400 years, molecular anthropology covers most of human history.
Traditional Anthropology relied on archaeology (the study of things left behind by humans long after they have perished) as well as paleontology (the study of bones and other anatomical parts) to draw conclusions about human life.
Now anthropology draws on additional layer of information provided by molecular biology, which is the study of the structure and function of the large molecules of living organisms. Knowledge of molecules by no means replaces the importance of archaeology or paleontology. It enhances knowledge by introducing another layer, at times confirming what we know from the study of things and bones, and at times questioning it and raising critical debate.
Therefore, molecular anthropology stands at the cutting edge of modern biology and the social sciences. UCT human genetics professor Raj Ramesar calls it the ‘crossings’ in modern knowledge systems between natural, health and social sciences, as well as the humanities.
It is the field that brings to us scientific ancestry testing. A growing business worldwide, everyone is interested in their ancestry. Our first curiosity when we meet one another is to decipher where we come from.
Spencer Wells’ Genographic Project, a collaboration between National Geographic and IBM, tested my female line of ancestry and revealed that I share a common ancestor with people who presently live in northern India and southern Pakistan.
For this test, they took a cheek swab of cells and looked at the molecular structure of what is known as mitochondrial DNA, the energy producing bits found in the cytoplasm of the cell. Biologists are able to identify – and date – changes in DNA and RNA over time and, by reading history backwards, establish a clock in evolution.
I recently received the results of another series of tests from South Africa ‘s guru in the field, Himla Soodyall. Soodyall is a professor at the University of the Witwatersrand and works for the National Health Laboratory Service. She had another look at my mitochondrial DNA and confirmed earlier findings. She also looked at my Y chromosome to test the male line and this is what she found: I bear the genetic signature of a population that originated in the Iberian Peninsula and expanded into Western Europe after the last ice age about 13,000 years ago. Haplogroup R-M207 (haplogroup is a fancy word for a unique packet of genes) is a Eurasian lineage dominant among western European populations. Soodyall writes: ‘The frequency of R-M207 is about 65% in South African whites and 17.4% in South African Indians.’ So, I am a South African of Iberian-Indian descent.
Molecular anthropology is able to confirm too that we are the descendents of a single line of human beings and that, at no time have we successfully cross-bred with members of our larger family like the Neanderthals. The idea that we constitute ‘races’ is now unquestionably a myth especially as gene flow has reached even the most isolated populations today.
Molecular biology has powerfully influenced other academic disciplines too. There is a new field molecular psychiatry, an effort to better understand – and treat – mental disease by examining how molecules malfunction in the brain. Evolutionary psychology puzzles over the biochemistry of our emotional states and how those have come about, including love and hate, laughter and anger. The neuropsychology of music – why our brains enjoy listening to the various patters of music – is a field of research at one of the foremost music conservatories in the USA and music students are required to take courses in brain science too.
My own discipline which is sociology has begun to wake up to the powerful reality of molecular biology. Douglas Massey gave his presidential speech at a gathering of the American Sociological Association beseeching his colleagues to understand the biology of the machine that directs human behaviour, which is our almighty brain! Economics is modeling human market behaviour based on the evolutionary biology of cooperation, altruism and conflict.
* Wilmot James is Chief Executive of the Africa Genome Education Institute and UCT Honorary Professor in the Division of Human Genetics.