Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Color differences within and between species have common genetic origin

23.10.2009
Spend a little time people-watching at the beach and you're bound to notice differences in the amount, thickness and color of people's body hair. Then head to the zoo and compare people to chimps, our closest living relatives.

The body hair difference is even more pronounced between the two species than within our own species.

Do the same genes cause both types of variation? Biologists have puzzled over that question for some time, not just with respect to people, chimps and body hair, but for all sorts of traits that differ within and between species. Now, a study by University of Michigan researchers shows that, at least for body color in fruit flies, the two kinds of variation have a common genetic basis. The research, led by evolutionary biologist Patricia Wittkopp, appears in the Oct. 23 issue of the journal Science.

Wittkopp's group explored the genetic underpinnings of pigmentation differences within and between a pair of closely related fruit fly species: Drosophila americana, which is dark brown, and Drosophila novamexicana, which is light yellow.

"We started by asking which parts of the genome contribute to the pigmentation difference between species," said Wittkopp, an assistant professor of ecology and evolutionary biology. Genetic mapping narrowed the search to two regions that happened to contain genes already known to affect pigmentation. The researchers then focused on one particular gene, known as tan, and used fine-scale genetic mapping to determine that evolutionary changes in that specific gene, not another gene in the same region, have contributed to the pigmentation difference.

To confirm that finding, the team transferred copies of the tan gene from the yellow species into flies of a completely different species, Drosophila melanogaster, and then did the same thing with copies of the tan gene from the brown species. The only difference between the two groups of altered flies was the transferred gene, "and that difference was enough to result in pigmentation differences," Wittkopp said.

Confident that the tan gene was responsible for part of the color difference between species, Wittkopp and coworkers investigated color variation within the brown species. Some flies in that species are noticeably darker than others, and previous experiments have suggested that the basis for the difference is genetic, rather than environmental.

Again using genetic mapping, the researchers found evidence that the tan gene also contributes to color variation among individuals within the brown species. Going a step further, they showed that it is not just the same gene that contributes to color differences within and between species, but also the same genetic changes within this gene. Currently, the team is trying to pinpoint the exact genetic change (or changes) within the tan gene that is responsible for the color shift.

Although this study focused on fruit flies, the work could lead to better understanding of patterns of variation throughout nature, Wittkopp said. "We're using a model system, but when you get down to the basic mechanisms of inheritance---how information is passed from one generation to the next---the process is essentially the same in all living things. While we can't extrapolate about the specific genes involved, it is fair to say that mutations contributing to both variation within species and divergence between species may be a common source of evolutionary change."

Wittkopp's coauthors on the Science paper were undergraduate students Emma Stewart, Laura Shefner, Gabriel Smith-Winberry, Saleh Akhras and Elizabeth Thompson; graduate student Lisa Arnold; and technicians Adam Neidert and Belinda Haerum.

The researchers received funding from the National Science Foundation, the Margaret and Herman Sokol Endowment for Faculty and Graduate Student Research and the University of Michigan.

For more information:
Wittkopp: www.eeb.lsa.umich.edu/eeb/people/wittkopp/index.html
Science: -http://www.sciencemag.org/

Nancy Ross-Flanigan | EurekAlert!
Further information:
http://www.umich.edu

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>