By Avigayil Kadesh What caused the male mice in Dr. Haim Cohen’s
lab at Bar-Ilan University to live 15 percent longer than usual?
It was extra doses of a gene called Sirtuin 6, or SIRT6 for
short. And why didn’t it have the same effect on the female
mice? Stay tuned for further research from the Israeli team
headed by the molecular biologist. As described in the February
22 online issue of the popular science journal Nature , seven
types of sirtuin genes are thought to encode a class of proteins
found in every species from single-celled yeast to complex
humans. Scientists had previously shown that removing SIRT1 from
yeast, worms and flies caused faster aging and earlier death,
while transplanting a copy of SIRT1 increased their life
expectancy. Cohen wanted to see the effect of sirtuins in
mammals. A 2006 study demonstrated that mice lacking SIRT6 aged
more quickly, developing spinal curvature, calcium deficiency,
osteoporosis, immune system problems and diabetes. Perhaps, he
reasoned, an abundance of SIRT6