Why women outlive men

Health

more>>

Facebook users really 'liked' organ donor option

Adding an organ donation option to the average Facebook user's profile prompted a dramatic rise in potential donors, researchers report.

Could 'moderate' drinking be safe during pregnancy?

Children of women who drink moderate amounts of alcohol while pregnant don't appear to have any neurodevelopmental problems when it comes to balance, a new British study suggests.

Concussion damage looks much like early Alzheimer's

Concussion can lead to damage in the white matter of the brain that resembles abnormalities found in people in the early stages of Alzheimer's disease, a new study suggests.

Many Americans want health care via smartphone

Plenty of Americans are eager to use their mobile phones and tablet computers to better manage their health care, a new poll finds -- though the nation has a way to go before we're all consulting Dr. Smartphone.

Scans uncover dangerous hardening of abdominal aorta

People with a "hardening" of the abdominal aorta are at increased risk for heart attack and stroke, according to a new study.

Minority kids with autism less likely to use specialty services

Black and Hispanic children with autism are markedly less likely than children from white families to receive specialty care for complications tied to the disorder, a new study finds.

Skipping breakfast may raise diabetes risk

Eating breakfast every day may help overweight women reduce their risk of diabetes, a small new study suggests.

Tobacco laws for minors may cut adult smoking as well

Strict controls on the sale of cigarettes to youth may also reduce adult smoking, a new study suggests.

Sibling bullying can lead to depression, anxiety in victims

Being picked on by your brother or sister may seem like a normal part of growing up, but for some kids the bullying may be a source of depression and anxiety, a new study suggests.

Video gamers may have better visual recall

In a new finding sure to be shared with some skeptical parents, it seems that the brains of video game enthusiasts make better and faster use of visual input.

THURSDAY, Aug. 2 (HealthDay News) -- New research reveals that mutations to the DNA of the mitochondria cause men to age faster than women -- a finding that may explain why women, on average, outlive men.

The researchers from Monash University in Australia examined male and female fruit flies that carried mitochondria -- the part of the cell that converts food into energy -- of various origin. They found that genetic variation in the mitochondria predicted life expectancy in males, but not in females. The investigators concluded that several mutations within the DNA of mitochondria affect how quickly men age as well as their longevity.

"Intriguingly, these same mutations have no effects on patterns of aging in females. They only affect males," Dr. Damian Dowling, from the Monash School of Biological Sciences, said in a university news release. "All animals possess mitochondria, and the tendency for females to outlive males is common to many different species. Our results therefore suggest that the mitochondrial mutations we have uncovered will generally cause faster male aging across the animal kingdom."

The mutations result from the way mitochondrial genes are passed down from one generation to the next, the study authors noted.

"While children receive copies of most of their genes from both their mothers and fathers, they only receive mitochondrial genes from their mothers. This means that evolution's quality control process, known as natural selection, only screens the quality of mitochondrial genes in mothers," explained Dowling. "If a mitochondrial mutation occurs that harms fathers, but has no effect on mothers, this mutation will slip through the gaze of natural selection, unnoticed. Over thousands of generations, many such mutations have accumulated that harm only males, while leaving females unscathed."

The study authors said they plan to continue their research and explore ways to negate the genetic mutations that negatively affect men's life expectancy.

The study was published Aug. 2 in Current Biology.

More information

The U.S. National Library of Medicine has more about genetics.

*DISCLAIMER*: The information contained in or provided through this site section is intended for general consumer understanding and education only and is not intended to be and is not a substitute for professional advice. Use of this site section and any information contained on or provided through this site section is at your own risk and any information contained on or provided through this site section is provided on an "as is" basis without any representations or warranties.