Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Earth Science News .




ABOUT US
It's in our genes: Why women outlive men
by Staff Writers
Melbourne, Australia (SPX) Aug 06, 2012


File image.

Scientists are beginning to understand one of life's enduring mysteries - why women live, on average, longer than men. Published in Current Biology, research led by Monash University, describes how mutations to the DNA of the mitochondria can account for differences in the life expectancy of males and females. Mitochondria, which exist in almost all animal cells, are vital for life because they convert our food into the energy that powers the body.

Dr Damian Dowling and PhD student, Florencia Camus, both from the Monash School of Biological Sciences, worked with Dr David Clancy from Lancaster University to uncover differences in longevity and biological ageing across male and female fruit flies that carried mitochondria of different origins.

They found that genetic variation across these mitochondria were reliable predictors of life expectancy in males, but not in females.

Dr Dowling said the results point to numerous mutations within mitochondrial DNA that affect how long males live, and the speed at which they age.

"Intriguingly, these same mutations have no effects on patterns of ageing in females. They only affect males," Dr Dowling said.

"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 ageing across the animal kingdom."

The researchers said these mutations can be entirely attributed to a quirk in the way that mitochondrial genes are passed down from parents to offspring.

"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," Dr Dowling said.

"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 builds on previous findings by Dr Dowling and his team that investigated the consequences of maternal inheritance of mitochondria in causing male infertility.

"Together, our research shows that the mitochondria are hotspots for mutations affecting male health. What we seek to do now is investigate the genetic mechanisms that males might arm themselves with to nullify the effects of these harmful mutations and remain healthy," Dr Dowling said.

.


Related Links
Monash University
All About Human Beings and How We Got To Be Here






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ABOUT US
Later Stone Age got earlier start in South Africa than thought
Boulder CO (SPX) Aug 03, 2012
The Later Stone Age emerged in South Africa more than 20,000 years earlier than previously believed - about the same time humans were migrating from Africa to the European continent, says a new international study led by the University of Colorado Boulder. The study shows the onset of the Later Stone Age in South Africa likely began some 44,000 to 42,000 years ago, said Paola Villa, a cura ... read more


ABOUT US
FEMA cell-phone alerts warn too many

Queen, politicians, Nobel winner named to UN social panel

Sri Lanka navy urges Australia to deport boatpeople

Samurai festival returns to disaster-hit Japan

ABOUT US
EU fights to catch Chinese in Greenland rare-earths goldrush

Apple co-founder Wozniak sees trouble in the cloud

You and your smartphone bill

Too cool to follow the law

ABOUT US
France's Veolia boosts cost cutting, stock tumbles

Earth absorbs more of our CO2 emissions: science

Spillways can divert sand from river to rebuild wetlands

Coral reef thriving in sediment-laden waters

ABOUT US
Aerial photos reveal dynamic ice sheet

Russian icebreaker sets out for expedition

Researchers analyze melting glaciers and water resources in Central Asia

Who owns the North Pole?

ABOUT US
Roots and microbes: Bringing a complex underground ecology into the lab

India's economic growth seen lower as rains play truant

Early weaning, DDGS feed could cut costs for cattle producers

UCLA research makes possible rapid assessment of plant drought tolerance

ABOUT US
India floods kill 34, hundreds of pilgrims stranded

Jamaica braces for Tropical Storm Ernesto

Ernesto churns towards Mexico, Central America

N. Korea says floods killed 169, left 400 missing

ABOUT US
Gunmen kill 2 sailors, kidnap 4 foreigners in Nigeria

France would back African intervention in Mali: minister

Suicide bomber in Nigeria kills at least 6 soldiers

Mali wives prevent loyalist soldiers' arrest

ABOUT US
It's in our genes: Why women outlive men

Later Stone Age got earlier start in South Africa than thought

Modern culture 44,000 years ago

Hey, I'm over here: Men and women see things differently




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement