Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Genetic Differences Influence Aging Rates in the Wild

13.12.2007
Long-lived, wild animals harbor genetic differences that influence how quickly they begin to show their age, according to the results of a long-term study reported online on December 13th in Current Biology, a Cell Press publication.

Evidence for the existence of such genetic variation for aging rates—a central tenet in the evolutionary theory that explains why animals would show physiological declines as they grow older—had largely been lacking in natural populations until now, the researchers said.

“We’ve found that individuals differ in their rates of aging, or senescence, and that these differences are (at least in part) caused by genetic effects so they will be inherited,” said Alastair Wilson of the University of Edinburgh. “While the genetic effects we found are completely consistent with existing theory, scientists hadn’t previously managed to test this theory properly except in controlled laboratory experiments.

“We’ve also done this work on long-lived mammals,” he added. “For someone interested in the evolution of aging and senescence in humans, these are going to be more relevant organisms than Drosophila [fruit flies].”

... more about:
»Theory »Variation »effects »individual »selection

Scientists normally expect genetic mutations having bad effects to be removed by natural selection, Wilson explained. Conversely, selection will lead to an increase in the frequency of mutations that are beneficial. “On this basis, any genes with bad effects on survival or reproduction should be removed by selection,” he said. “But if that were true then there is no reason for individuals to deteriorate as they get old.”

Aging therefore raises a critical question: How has natural selection failed to remove genetic effects responsible for such reduced fitness among older individuals? Current evolutionary theory explains this phenomenon by showing that, as a result of the risk of death from environmental causes that individuals experience over the course of their lives, the force of selection inevitably weakens with age, he continued. This, in turn, means that genetic mutations having detrimental effects that are only felt late in life may persist in a population. Although widely accepted, this theory rests on the assumption that there is genetic variation for aging in natural systems.

To look for such genetic variation in the new study, the researchers examined wild Soay sheep and red deer living on two Scottish islands. Those populations were ideal for the study because they provide unparalleled levels of data, including individual survival and reproductive success, for large numbers of long-lived animals, Wilson said. In both study systems, individually marked animals are followed throughout their lives from birth until death, and their relationships to one another are known.

In both the red deer and sheep populations, they found evidence for age-specific genetic effects on “fitness”—a measure combining the animals’ probability of survival and reproduction. “The present study provides, to our knowledge, the first evidence for additive genetic variance in aging rates from a wild, non-model study organism,” the researchers concluded. “Furthermore, the age-specific patterns of additive genetic (co)variation evident in the two populations examined here were entirely consistent with the hypothesis that declines in fitness with age are driven by a weakening of natural selection.”

Cathleen Genova | alfa
Further information:
http://www.cell.com

Further reports about: Theory Variation effects individual selection

More articles from Life Sciences:

nachricht Fish recognize their prey by electric colors
13.11.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection
13.11.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection

13.11.2018 | Life Sciences

Fish recognize their prey by electric colors

13.11.2018 | Life Sciences

Ultrasound Connects

13.11.2018 | Awards Funding

VideoLinks
Science & Research
Overview of more VideoLinks >>>