Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Oral Bacteria Create a ‘Fingerprint’ in Your Mouth

25.10.2013
The bacteria in the human mouth – particularly those nestled under the gums – are as powerful as a fingerprint at identifying a person’s ethnicity, new research shows.

Scientists identified a total of almost 400 different species of microbes in the mouths of 100 study participants belonging to four ethnic affiliations: non-Hispanic blacks, whites, Chinese and Latinos.

Only 2 percent of bacterial species were present in all individuals – but in different concentrations according to ethnicity – and 8 percent were detected in 90 percent of the participants. Beyond that, researchers found that each ethnic group in the study was represented by a “signature” of shared microbial communities.

“This is the first time it has been shown that ethnicity is a huge component in determining what you carry in your mouth. We know that our food and oral hygiene habits determine what bacteria can survive and thrive in our mouths, which is why your dentist stresses brushing and flossing. Can your genetic makeup play a similar role? The answer seems to be yes, it can,” said Purnima Kumar, associate professor of periodontology at The Ohio State University and senior author of the study.

“No two people were exactly alike. That’s truly a fingerprint.”

Kumar used a DNA deep sequencing methodology to obtain an unprecedented in-depth view of these microbial communities in their natural setting.

When the scientists trained a machine to classify each assortment of microbes from under the gums according to ethnicity, a given bacterial community predicted an individual’s ethnicity with 62 percent accuracy. The classifier identified African Americans according to their microbial signature correctly 100 percent of the time.

The findings could help explain why people in some ethnic groups, especially African Americans and Latinos, are more susceptible than others to develop gum disease. The research also confirms that one type of dental treatment is not appropriate for all, and could contribute to a more personalized approach to care of the mouth.

“The most important point of this paper is discovering that ethnicity-specific oral microbial communities may predispose individuals to future disease,” Kumar said. Though it’s too soon to change dental practice based on this work, she said the findings show that “there is huge potential to develop chair-side tools to determine a patient’s susceptibility to disease.”

The research is published in the Oct 23, 2013, issue of the journal PLOS ONE.

Kumar and colleagues collected samples of bacteria from the saliva, tooth surfaces and under the gums of the study participants.

More than 60 percent of bacteria in the human mouth have never been classified, named or studied because they won’t grow in a laboratory dish, so the researchers identified the different species – or species-level operational taxonomic units – by sequencing their DNA.

The DNA sequences represented 398 units overall, with an average of about 150 different species per person.

Using only the bacteria found under the gums – which are called subgingival microbes – the classifying machine performed best at positively identifying African Americans according to their microbial communities, followed by positive identifications of Latinos at 67 percent and Caucasians at 50 percent – but with 91 percent specificity, meaning the classifier determined how often a sample did not come from a white person 91 percent of the time.

Kumar and colleagues then expanded the selection of total microbes in all areas of the mouth, and identified surrogate communities of bacteria that were present in at least 80 percent of participants of each ethnic group. These communities showed a prediction likelihood of 65 percent for African Americans, 45 percent for Caucasians, 33 percent for Chinese and 47 percent for Latinos.

“Nature appears to win over nurture in shaping these communities,” Kumar noted, because African Americans and whites had distinct microbial signatures despite sharing environmental exposures to nutrition and lifestyle over several generations.

Kumar and her colleagues have embarked on a multistudy investigation of the role the body’s microbial communities play in preventing oral disease. The group already has determined that smoking disrupts the healthy bacterial community in the oral cavity, giving disease-causing microbes easier access to the mouth.

Multiple diseases of the mouth are caused by bacterial infections, ranging from cavities to oral cancer.

Bacteria live together in communities called biofilms, and it’s within that infrastructure that they communicate with each other and with the immune system. A key to overall human health, Kumar said, is keeping those oral biofilms themselves in good health.

Kumar didn’t expect ethnicity to produce significant differences in the bacterial collection in the mouth. But the patterns became clear during the DNA analysis.

“The overarching goal here is to say, ‘If you’re healthy, are biofilms similar between individuals?’ We know, in fact, that they are not similar.

“Among healthy people, there is a core group of species everybody seems to have. But then there is personalization. What factors contribute to this personalization? Gender, age, other parts of genetics?”

It did make sense to Kumar that bacteria below the gums are most closely linked to ethnicity identification because they are the least likely to be disrupted by environmental changes in the mouth, such as food, toothpaste and tobacco.

“Bacteria under the gum line are protected but are also the first opportunity your body gets to be educated about the bacteria that hang out in your mouth,” she said.

The power of bacteria in the body remains misunderstood to some extent. Though many people are inclined to blame disease susceptibility on lifestyle and behavior, this work suggests that humans can be predisposed to certain disease risks solely because of the microbes that set up shop in their mouths.

“We underestimate these bugs and their power to do good and evil to us. As long as we harness their good side, we’re healthy,” she said.

Exercise, healthful eating, avoiding smoking, brushing and flossing the teeth, preventing diabetes and obesity – all of these factors are in our control, she explained. But when it comes to genetic factors, Kumar said, “It makes you want to ask: ‘Am I in charge or not?’”

This research was supported by an Ohio State University College of Dentistry training grant and the National Institute of Dental and Craniofacial Research.

Co-authors include Matthew Mason of the Division of Oral Biology, Haikady Nagaraja of the College of Public Health Division of Biostatistics and Terry Camerlengo of the Comprehensive Cancer Center, all at Ohio State; and Vinayak Joshi of Maratha Mandal Dental College of Belgaum, India.

Contact: Purnima Kumar, (614) 247-4532; Kumar.83@osu.edu
Written by Emily Caldwell, (614) 292-8310; Caldwell.151@osu.edu

Emily Caldwell | Newswise
Further information:
http://www.osu.edu

More articles from Studies and Analyses:

nachricht Real-time feedback helps save energy and water
08.02.2017 | Otto-Friedrich-Universität Bamberg

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>