A contender for the elusive fountain of youth: an enzyme found in humans appears to lengthen the life of mice. Researchers hoping to slow the march of age were dealt a blow in 2010, when signs that an enzyme called sirtuin 2 extended the life of worms were shown to be false due to flawed experimental design.

Mammals have seven types of sirtuin, so Haim Cohen and Yariv Kanfi at Bar-Ilan University in Ramat Gan, Israel, turned to sirtuin 6 instead. They compared mice genetically engineered to have increased levels of SIRT6 with normal mice, engineering the mice in two different ways to control for genetic influences.

Male mice from both strains lived 15 per cent longer than normal mice or females. Older modified male mice metabolised sugar faster than normal mice and females, suggesting that SIRT6 might extend life by protecting against metabolic disorders such as diabetes …

A chemical in the brain controls sexual preference in mice, according to scientists in China.

Male mice bred without serotonin lose their preference for females, a report in Nature says.

The researchers say it is the first time that a neurotransmitter has been shown to play a role in sexual preference in mammals.

Experts have warned about the dangers of drawing conclusions about human sexuality.

The research team first bred male mice whose brains were not receptive to serotonin.

A series of experiments demonstrated that these mice had lost the preference for females shown by unmodified males.

When presented with a choice of partners, they showed no overall preference for either males or females…

UPPER DARBY, Pa. – A pizzeria owner with mice problems he blamed on competitors tried to sabotage two rival shops by dumping mice in them Monday, authorities in suburban Philadelphia said…