/ 2 June 2004

Home-grown number cruncher

Mathematicians have a reputation of being socially awkward creatures whose obscure work does not necessarily have a lot to offer the real world. 

However, Dr Gareth Witten — who is in the running for a National Science and Technology Forum award on May 28 — is practically a party animal. He speaks understandable garden-variety English, plays beach volleyball and, last but not least, is using his skills for something extremely relevant: the fight against Aids.

The 32-year-old is up for an award in a new category honouring up- and-coming black researchers, which suggests that home-grown number-crunching talent is on the increase.

Among his competitors are two other mathematicians, Professor Mark Petersen of the North West University and Dr Mamokgethi Setati of Wits, who is the first black female to receive a Phd in mathematics education.

Witten’s specialty is biomathematics, the little-known marriage between medicine and numbers. The University of Cape Town lecturer uses his particular skills, encouraged by his parents, to try to understand the life cycle of the fiendishly complicated retrovirus. The constantly shifting shapes of the virus have become his key to understanding another puzzle: our immune system.

“I want to understand HIV at a cellular level,” he says. “So I develop mathematical models of the interactions of the virus and the immune system.”

Immune systems are complex, and have no central controllers. Under threat, they can behave in unexpected ways to combat threats. Neurologists often only understand how the brain works by studying what happens when it doesn’t, for example in stroke victims. In the same way, Witten can gain clues about how our immune systems operate by looking at what happens when they are riddled with viruses.

His research is specifically targeted at Africa. There is already data from the United States and Europe on the HI virus. But it’s not the subtype common to sub-Saharan Africa. “We have a strong feeling that either the virus or our immune systems may behave differently,” he says. 

Biomathematics is the fastest-growing field in mathematics. But South Africa lags far behind developed countries such as the US, Europe and Australia.

“Our biologists do not have good mathematics training and our mathematicians, generally, have a very poor perspective of biology,” he explains. “It is difficult to break the mould. People prefer to explore their isolated research fields. My biggest challenge is to break that mould because biological questions provide big challenges for mathematicians. But many people won’t change.”