Study shows genetic differences between uptown and downtown rats living in Manhattan

December 4, 2017 by Bob Yirka report

(Phys.org)—A small team of researchers from Fordham University and Providence College, both in the U.S., has found that there are small but discernible genetic differences between rats living uptown versus downtown on the island of Manhattan. In their paper published in the journal Molecular Ecology, the group describes trapping rats from one end of the island to the other, conducting genetic tests on them and outlining what they found.

New York City, like other major cities in the world, hosts a very large population of rats—in this case, mostly brown rats. Most people that live there find them to be a problem, because in addition to being destructive and carriers of disease, they are also considered to be disgusting. In this new effort, the researchers sought to learn more about the rats that live only on Manhattan Island, noting that little work has been done to understand the rats that live there.

The study consisted of trapping rats, moving north to south on the island, cutting off their tails, and using them as a source for DNA analysis—and then comparing the genomic results by geography.

The researchers report that the vast majority of the rats were descendants of rats from western Europe—brought over on ships over 200 years ago. But the analysis also revealed that the rats have been in the area long enough to have developed minor genetic differences depending on where they lived. This, the team notes, was not particularly surprising due to rat behavior—they rarely stray far from home. Nor was it surprising to see differences between the uptown and downtown rats—the two areas are separated by the commercial district, which is not particularly favorable to rats. Thus, those that live uptown have little incentive to move downtown, or vice-versa. Surprisingly, the analysis showed that there were even slight differences between neighborhoods—each had their own distinct rats. The researchers could tell, for example, by looking at an individual rat profile, if it had resided in the East or West Village.

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Genetic differences among monkeys in Tanzania show troubling pattern

Research taps region's landscapes to explain how human activities are affecting an already endangered species

Date:October 5, 2015

Source:University of Oregon

An endangered monkey species in Tanzania is living in geographical pockets that are becoming isolated from one another. The situation, researchers say, is mostly driven by the monkeys' proximity to villages and the deliberate burning of forests to make way for crops and pastures.

An international team, led by Maria Jose Ruiz-Lopez, a postdoctoral researcher at the University of Oregon, combed five distinct forested areas from 2011 to 2012. Gathered were 170 fecal samples of the Udzungwa red colobus monkey (Procolobus gordonorum), for DNA analyses. These monkeys are considered an indicator species of ecological change.

The region studied has fertile soils and forests scattered in valleys and along mountain ridges in the Eastern Arc Mountains, part of a vast region known as the Eastern Afromontane Hotspot. It is home to many plants and animals that live nowhere else in the world.

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Human-Chimp Genetic Differences: New Insights Into Why Humans Are More Susceptible to Cancer and Other Diseases

ScienceDaily (Aug. 23, 2012) — Ninety-six percent of a chimpanzee's genome is the same as a human's. It's the other 4 percent, and the vast differences, that pique the interest of Georgia Tech's Soojin Yi. For instance, why do humans have a high risk of cancer, even though chimps rarely develop the disease?

In research published in September's American Journal of Human Genetics, Yi looked at brain samples of each species. She found that differences in certain DNA modifications, called methylation, may contribute to phenotypic changes. The results also hint that DNA methylation plays an important role for some disease-related phenotypes in humans, including cancer and autism.

"Our study indicates that certain human diseases may have evolutionary epigenetic origins," says Yi, a faculty member in the School of Biology. "Such findings, in the long term, may help to develop better therapeutic targets or means for some human diseases. "

Read on:  http://www.sciencedaily.com/releases/2012/08/120823142735.htm