Scientists find ageing gene is linked to immunity

LONDON, (Reuters) – British scientists studying the  genetics of ageing said yesterday that experiments on  laboratory worms showed that a specific gene is strongly linked  to lifespan, immunity and disease resistance.

Since the gene, called DAF-16 in worms, is found in many   animals and in humans, the finding could open up new ways to  affect ageing, immunity and resistance in humans, the scientists  said.

“We wanted to find out how normal ageing is being governed  by genes and what effect these genes have on other traits, such  as immunity,” said Robin May of the University of Birmingham,  who led the study.

Populations across the world are ageing at a staggering  pace, posing potentially big challenges for health and social  care systems. A study by Danish scientists last year found that  half of babies born in the rich world today will live to  celebrate their 100th birthdays.

Scientists are keen to find out how people age to try to  develop drugs to help them stay healthier as their lives extend.

“What we have found is that things like resistance and  ageing tend to go hand in hand,” May said in an interview.

May’s team compared longevity, stress resistance and  immunity in four related species of worm. They also looked for  differences in the activity of DAF-16 in each of the four  species, and found that they were all quite distinct.

Importantly, the differences in DAF-16 corresponded to  differences in longevity, stress resistance and immunity between  the four species, with higher levels of DAF-16 activity  correlating to longer life, increased resistance and better  immunity against some infections.

May said DAF-16 was active in most cells in the body and was  very similar to a group of human genes called FOXO genes, which  scientists believe play a role in the ageing process.

“The fact that subtle differences in DAF-16 between species  seem to have such an impact on ageing and health is very  interesting and may explain how differences in lifespan and  related traits have arisen during evolution,” May said.

The study was published in the Public Library of Sciences  (PLoS) One journal.

In a commentary on the study, Professor Douglas Kell of the  Biotechnology and Biological Sciences Research Council (BBSRC),  which funded the work, said the findings would help scientists  understand some of the mechanisms that determine how humans age.

“It is very important to develop a good understanding of  healthy ageing if we are to appreciate what happens to an older  person’s physiology when they become unwell or experience  difficulties with everyday tasks such as recalling memories or  moving around,” he wrote.