Poor eyesight quashed Mahendra Rao's early ambitions of becoming an air-force pilot, but his training as a medical officer at Bombay University steered his path to the United States — and a new vision of using stem cells in medicine. (See CV)

While a resident in clinical medicine and neurology, Rao realized there were few treatments for his patients, so he turned to research. He left India for a PhD in neurobiology at the California Institute of Technology in Pasadena. Although a difficult career decision, given the change in lifestyle and income, it gave him the chance to work with leading biologists such as Paul Patterson. In Patterson's lab, Rao isolated neural-crest stem cells, the cells that regulate development of the peripheral nervous system.

Patterson also helped Rao forge future collaborations, notably conducting his postdoc at Case Western Reserve University in Cleveland, Ohio, with Story Landis, now director of the National Institute of Neurological Disorders and Stroke. There, Rao focused on factors affecting the fate of stem cells. Finding opportunities to exploit new technology was also part of Rao's strategy. Rao joined the University of Utah's school of medicine as an assistant professor, in part because it housed the first centre to generate transgenic mice using embryonic stem cells — a logical fit with his work demonstrating the relationships between the stages of stem-cell development.

After five years at Utah, Rao became an adjunct faculty member at the National Centre for Biological Sciences in Bangalore, India, where he continues to teach courses. It was his 2001 move to the US National Institute of Aging, however, that paired his stem-cell research with studies of mortality. The signalling mechanisms that regulate stem cells' ability to escape death change during ageing and age-related neurodegenerative disorders.

But federal restrictions on the use of stem cells slowed his work and eventually triggered a move to Invitrogen, where he will have freedom to pursue his research interests. “It's unlikely that I would have gone to industry without the current policy decisions,” says Rao. “But, in California, I saw people who wanted to make it work rather than worrying about breaking the law.”

Rao remains hopeful that one day the US federal government will support stem-cell research. Until then, he hopes others won't be deterred from pursuing their own interests in that area. “Do what you love, because it's what you will do best,” he says.