A gene involved in Down's syndrome may protect against cancer, despite having been thought to be a cause of the disease. From tests on mice, Johns Hopkins University researchers have found that those with extra copies of a particular chromosome, such as Down's syndrome sufferers, are less likely to develop intestinal cancer and have smaller tumours. The chromosome includes a gene, Ets2, suspected of causing cancer. But when there is an extra copy, it appears to repress tumours, WebMD reports. The researchers say more testing is required, but they hope to develop a drug that will boost Ets2.

Cocaine vaccine in the pipeline

A US-based husband-and-wife team is working on a cocaine vaccine that attacks the drug's molecules, blocking the high. Because most drug molecules are so small, the body's immune system is unable to recognise them and make antibodies. The vaccine being developed by Tom and Therese Kosten of Baylor College of Medicine in Houston circumvents the difficulty of rewiring reward pathways in the brain that are hijacked by drugs such as cocaine, AP reports. Instead, it triggers the body to produce antibodies that bind to the cocaine and stop it reaching the brain.

Allergies blocked by breastfeeding

Breastfeeding for at least four months or using infant formula without cow-milk protein may prevent or delay eczema, and possibly asthma and food allergies in high-risk infants, according to a report from the American Academy of Paediatrics. 'The best prevention ... is exclusive breastfeeding for four months,' says author Frank Greer. The diet of pregnant or lactating women doesn't seem to offer any particular protection, nor does the timing of introducing solids into an infant's diet, HealthDay.com reports.

Mother's milk allays stress in kids

Breastfeeding also may help make children more stress-resilient, say researchers who have analysed a decade's worth of data from almost 9,000 children born in Britain in 1970. Breastfed children are significantly less anxious than those who have not been, HealthDay.com reports. The study tried to replicate research showing that close physical contact between animal mothers and their babies may have a positive impact on the offsprings' stress responses. Team leader Scott Montgomery says breastfeeding itself may not be the cause - mothers who breastfeed may simply have a better relationship with their child.

Fingers point to osteoarthritis risk

If your ring finger is longer than your index finger, you may be three times as likely to suffer from knee osteoarthritis if you're a woman, and almost twice as likely if you're a man, say University of Nottingham researchers who studied more than 3,000 people. Other osteoarthritis risk factors such as age, body-mass index and physical activity don't explain the correlation, WebMD reports. The researchers say they're not sure how to explain their findings, other than that hormonal factors may be involved.