Mutations that matter

(Medical Xpress)—Identifying the genetic source of a specific trait can be a little like finding a needle in a field full of haystacks. University of Dayton biologist Thomas Williams is working to shrink the number of haystacks.

In a new study, published by PLoS Genetics, Williams and his lab team were able to single out a specific sequence in the genetic code of a fruit fly where changes to the code resulted in a different pigmentation pattern between flies of the same and related species. So out of the whole fly —more than 15,000 genes and even more genetic "switches"— causing similar pigmentation changes occurred in the same switch.

"Scientists have mapped the genomes of humans and several animals, yet our understanding of how that information is stored and how it produces traits is woefully inadequate," Williams said. "There are literally millions of places where changes occur, but only thousands of places where it matters."

By studying the fruit fly as a model, Williams hopes to identify prime genetic "real estate"—those locations in the genome where mutations are most likely to have a significant impact, either positive or negative. Other scientists can then use that knowledge to focus studies on similar places in the , possibly identifying sections of the code where changes can pose or .

"We want to save time and money," Williams said. "We want to help others distinguish the signals from the noise."

It is common knowledge in the scientific community that genomes include the information for genes, which make a product that does something, Williams said. Less well known is that information is encoded in sequences that act as "switches" to tell genes when—and in which cells—to make their product.

The location for mutations occurs randomly in genomes. Many of these mutations are neutral, with no measurable effect on encoded information. Some mutations degrade information, leading to disease or disease risk. And some mutations modify information in useful ways.

"The great challenge for the era is to determine which mutations are neutral, injurious or beneficial," Williams said. "This difficulty is especially challenging for so-called genetic 'switches.' "

The paper, titled "Recurrent Modification of a Conserved Cis-Regulatory Element Underlies Fruit Fly Pigmentation Diversity," was published Aug. 29 by PLoS Genetics.

More information: www.plosgenetics.org/article/i… journal.pgen.1003740

Related Stories

'Wildly heterogeneous genes'

Sep 15, 2013

Cancer tumors almost never share the exact same genetic mutations, a fact that has confounded scientific efforts to better categorize cancer types and develop more targeted, effective treatments.

Painting by numbers

Jun 11, 2013

Individuals of a particular species generally differ from one another. We are clearly most adept at recognizing members of our own species, although dog and cat owners will be ready to confirm that their ...

Recommended for you

Stress reaction may be in your dad's DNA, study finds

Nov 21, 2014

Stress in this generation could mean resilience in the next, a new study suggests. Male mice subjected to unpredictable stressors produced offspring that showed more flexible coping strategies when under ...

More genetic clues found in a severe food allergy

Nov 21, 2014

Scientists have identified four new genes associated with the severe food allergy eosinophilic esophagitis (EoE). Because the genes appear to have roles in other allergic diseases and in inflammation, the ...

Brain-dwelling worm in UK man's head sequenced

Nov 20, 2014

For the first time, the genome of a rarely seen tapeworm has been sequenced. The genetic information of this invasive parasite, which lived for four years in a UK resident's brain, offers new opportunities ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.