Only 30 percent of human genes, which are traditional hallmarks of aging, may be directly involved in the process of aging, finds a study led by an Indian-American researcher at the US National Institutes of Health (NIH). The study suggests scientists may need to rethink which genes actually control aging. To understand, the researchers fed fruit flies with antibiotics and monitored the lifetime activity of hundreds of genes that scientists have traditionally thought control aging.

To their surprise, the antibiotics not only extended the lives of the flies but also dramatically changed the activity of many of these genes. Their results suggested that only about 30 percent of the genes traditionally associated with an aging set an animal's internal clock while the rest reflect the body's response to bacteria.

For the study, the team raised newborn male flies — of a type of fruit fly called Drosophila — on antibiotics to prevent bacteria growth.

Photo by Glen Hodson on Unsplash

"For decades, scientists have been developing a hit list of common aging genes. These genes are thought to control the aging process throughout the animal kingdom, from worms to mice to humans," said Edward Giniger, from the NIH's National Institute of Neurological Disorders and Stroke (NINDS). "We were shocked to find that only about 30 percent of these genes may be directly involved in the aging process. We hope that these results will help medical researchers better understand the forces that underlie several age-related disorders," he added. The findings are published in the journal iScience.

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For the study, the team raised newborn male flies — of a type of fruit fly called Drosophila — on antibiotics to prevent bacteria growth. At first, they thought that the antibiotics would have little or no effect. But, when they looked at the results, they saw something interesting. The antibiotics lengthened the fly's lives by about six days, from 57 days for control flies to 63 for the treated ones. "This is a big jump in age for flies. In humans, it would be the equivalent of gaining about 20 years of life," said lead author Arvind Kumar Shukla, a post-doctoral researcher at the varsity.

"We were totally caught off guard and it made us wonder why these flies took so long to die," Shukla added. Shukla and his team looked for clues in the genes of the flies. They used advanced genetic techniques to monitor gene activity in the heads of 10, 30, and 45-day old flies. "At first, we had a hard time believing the results. Many of these genes are classical hallmarks of aging and yet our results suggested that their activity is more a function of the presence of bacteria rather than the aging process," said Shukla. (IANS/JC)