Featured Research

from universities, journals, and other organizations

Fruit Fly Aggression Studies Have Relevance To Humans, Animals

Date:
September 23, 2006
Source:
North Carolina State University
Summary:
Researchers in the North Carolina Sate University genetics department have identified a suite of genes that affect aggression in the fruit fly Drosophila melanogaster, pointing to new mechanisms that could contribute to abnormal aggression in humans and other animals.

Fruit flies.
Credit: George Gilchrist, Clarkson University

Even the tiny, mild-mannered fruit fly can be a little mean sometimes – especially when there’s a choice bit of rotten fruit to fight over. And, like people, some flies have shorter tempers than others.

Researchers in the North Carolina Sate University genetics department have identified a suite of genes that affect aggression in the fruit fly Drosophila melanogaster, pointing to new mechanisms that could contribute to abnormal aggression in humans and other animals.

The study, led by doctoral student Alexis Edwards in the laboratory of Dr. Trudy Mackay, William Neal Reynolds Professor of Genetics, appears online in PloS Genetics.

Feisty flies themselves may not be very scary, but their genes and biochemistry have more in common with those of humans than the casual observer might suspect, and geneticists can subject flies to experiments that simply can’t be done on higher organisms.

To measure aggression, the researchers starved male flies for an hour and a half, then gave them a small food droplet and watched them duke it out, counting the number of times a focal fly would chase, kick, box, or flick his wings at other flies.

“Some animals will very vigorously defend their little food patch, whereas others are relatively polite,” Mackay said. “To determine if this had a genetic basis, we conducted a selection experiment.”

For the selection experiment, Edwards pulled three groups of flies – high aggression, low aggression and control – from the same baseline population, and kept them separate for 28 generations. From each generation, she selected the most aggressive flies from the high aggression group, the least aggressive flies from the low aggression group, and a random sample of the control flies, to be the parents of the next generation.

All the flies started at the same level of aggression, but after 28 generations of selection, the high aggression groups were kicking, chasing and boxing more often, while low aggression groups would hardly fight at all.

Selection experiments only show these kinds of results when there is some genetic control over the trait being selected. In this case, the genetic effect was not very strong – the heritability, or genetic contribution to, aggressive behavior was about 10 percent. The other 90 percent had to be attributed to environmental variation.

“This is definitely not genetic predeterminism,” Mackay said. “It’s a susceptibility. Even in flies, in the constant environment in which we grow them, the environment is more important than the genes. But we are very interested in that small genetic contribution.”

Next, the researchers wanted to know which specific genes affect a fly’s chances of becoming a bully. To find out, they conducted a microarray experiment, a way of comparing which genes are turned on or off, or up or down, in aggressive versus non-aggressive flies.

They found 1,539 genes that were expressed differently in the two groups – and flies only have about 14,000 genes in all. It will take more work to find out which of these genes directly affect aggressive behavior, which ones change as a result of the behavior, and how they do it.

But Edwards started by studying 19 families of flies, each of which had a single mutation in one of the genes identified in the microarray experiment. Fifteen of those 19 mutant families did, in fact, display abnormal aggression compared to non-mutants, confirming the role of those specific genes in aggressive behavior.

Those genes were already known to affect nervous system development, metabolism and immunity, among other things – but none of them had been previously implicated in aggression. Many of them have human counterparts.

“Now we have 15 completely novel genes we can use in the future to investigate aggressive behavior,” Mackay said. “Ultimately we hope to understand the basic biology of this very important trait, because the better we understand it in flies, the more we can develop logical human pharmaceutical interventions.”


Story Source:

The above story is based on materials provided by North Carolina State University. Note: Materials may be edited for content and length.


Cite This Page:

North Carolina State University. "Fruit Fly Aggression Studies Have Relevance To Humans, Animals." ScienceDaily. ScienceDaily, 23 September 2006. <www.sciencedaily.com/releases/2006/09/060920192543.htm>.
North Carolina State University. (2006, September 23). Fruit Fly Aggression Studies Have Relevance To Humans, Animals. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2006/09/060920192543.htm
North Carolina State University. "Fruit Fly Aggression Studies Have Relevance To Humans, Animals." ScienceDaily. www.sciencedaily.com/releases/2006/09/060920192543.htm (accessed October 21, 2014).

Share This



More Mind & Brain News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
Portable Breathalyzer Gets You Home Safely

Portable Breathalyzer Gets You Home Safely

Buzz60 (Oct. 21, 2014) Breeze, a portable breathalyzer, gets you home safely by instantly showing your blood alcohol content, and with one tap, lets you call an Uber, a cab or a friend from your contact list to pick you up. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Your Birth Season Might Determine Your Temperament

Your Birth Season Might Determine Your Temperament

Newsy (Oct. 20, 2014) A new study says the season you're born in can determine your temperament — and one season has a surprising outcome. Video provided by Newsy
Powered by NewsLook.com
Movies Might Desensitize Violence For Parents, Not Just Kids

Movies Might Desensitize Violence For Parents, Not Just Kids

Newsy (Oct. 20, 2014) A study suggests that parents become desensitized to violent movies as well as children, which leads them to allow their kids to view violent films. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins