Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mouse study suggests mammoth evolutionary change

22.05.2003


The white-footed mouse
Credit: Jim Schulz, Brookfield Zoo


A study of a common wild mouse by two University of Illinois at Chicago biologists has found evidence of dramatic evolutionary change in a span of just 150 years, suggesting genetic evolution can occur a lot faster than many had thought possible.
The findings are the first report of such quick evolution in a mammal and appear in the May 22 issue of the journal Nature.

Oliver Pergams, a conservation biology researcher with the Chicago Zoological Society in Brookfield, Ill. and visiting research assistant professor at UIC, conducted the research as his Ph.D. thesis project at UIC with Dennis Nyberg, associate professor of biology.


Pergams’ study began as a comparison of the genetics of two mice common to the Chicago region -- the white-footed mouse and the prairie deer mouse. But the search for historical samples quickly showed the white-footed mouse had squeezed out the prairie deer mouse from its dominant position, diminishing the samples needed to do a comparative study, so Pergams and Nyberg focused attention on the white-footed mouse.

"This intensified focus resulted in our discovery of rapid evolution," said Pergams. "It was a great surprise. We were simply trying to quantify the amount of genetic variation over time, not show evolution."

The researchers analyzed DNA samples taken from 56 museum specimens dating as far back as 1855, along with 52 recently captured mice from local forest preserves and state parks. Wayne Barnes, professor of biochemistry and molecular biophysics at the Washington University in St. Louis School of Medicine, assisted in analyzing the DNA.

The changes in gene sequence frequencies were dramatic, Pergams said, across the three 50-year intervals studied.

Only one of the mice from the latest period had the same DNA sequence as the most common sequence among the mice collected before 1950. The first mouse with the sequence currently common was captured back in 1906 at Volo Bog, some 45 miles northwest of Chicago. That discovery prompted Pergams to get all the museum specimens that were collected in Illinois’ Cook and Lake counties.

The researchers used DNA taken not from the nucleus, but from mitochondria, the power plants of the cell. Each cell contains many mitochondria, but only one nucleus.

"If you are working with very degraded, ancient DNA like that from museum skins, you are way ahead using this DNA with lots of copies," said Pergams. Mitochondrial DNA evolves much more rapidly than nuclear DNA, he said, though this evolution was previously thought only to occur over thousands of years.

"We did not expect to find the rapid, consistent and directional change that we did find," he said.

While evidence of such fast change has been cited in studies of fruit flies, this is the first reported study to document such quick evolution in a mammal.

What may account for this change?

"We think it likely that the new gene sequence was either unconditionally advantageous, or that it was advantageous relative to environmental changes caused by humans," Pergams said.

"Settlers may have brought in mice with the favorable gene that were able to out-compete mice with the native variant. A less likely possibility is that mice with these new gene sequences were already present, and that dramatic changes that humans caused in the environment allowed the new gene sequence to be selectively advantageous."

Since all the mice studied were caught in forest preserves and parks, Pergams and Nyberg consider the second alternative unlikely. Future studies should reveal if the favorable gene is in older mouse specimens held by museums in other parts of the country.

In any event, Pergams thinks this research may have broad implications.

"It suggests that humans are a likely cause of such rapid evolution," Pergams said, "and that much of current phylogenetic and phylogeographic methodology may be flawed because it does not take the possibility of rapid mitochondrial DNA evolution into account."

"It also suggests that the ’molecular clock’ may sometimes, and sporadically, tick blindingly fast."

Paul Francuch | EurekAlert!
Further information:
http://www.uic.edu/

More articles from Life Sciences:

nachricht Designer cells: artificial enzyme can activate a gene switch
22.05.2018 | Universität Basel

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>