Edmund Hilary may have been the first man to conquer Everest but soon his feat will be repeated by a band of mice. As well as making history, the mice may reveal the natural biochemical changes that take place at high altitude, which could lead to a test for athletes who have had their genes manipulated.
High-altitude training benefits athletes by stimulating production of erythropoietin (EPO), a hormone that allows blood to carry more oxygen. Yet it is possible to cheat by artifically boosting EPO levels, either by taking supplements or maybe by manipulating athletes' genes.
While today's tests can identify athletes who have taken artificial EPO, they cannot distinguish between EPO occurring naturally and as a result of gene interference. "Gene doping isn't yet in widespread use but it is important for those involved in anti-doping to stay one step ahead," says a spokesman for the anti-doping authority UK Sport.
Tejvir Khurana and colleagues at the University of Pennsylvania, Philadelphia, who began ascending Everest on Monday with the mice in tow, hope to find molecular "signatures" in the mice's tissue and blood that are only present if EPO is produced in the normal way. If present in humans, such markers could help develop a gene-doping test.
"The practical challenges they will face are fascinating," says Mike Grocott, an expert in extreme-environment physiology at University College London. "Parts of the ascent are technically difficult, particularly if you are carrying a mouse."