Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mixed population provides insights into human genetic makeup

16.02.2009
Genetic diseases and genetically mixed populations can help researchers understand human diversity and human origins according to a Penn State physical anthropologist.

"We wanted to get to a strategy to predict what a face will look like," said Mark D. Shriver, associate professor of biological anthropology. "We want to understand the path of evolution that leads to that part of the selection process."

To pinpoint genes that influence the shape of the human face and head, Shriver began with an online database of genes linked to disease -- Online Mendelian Inheritance of Man. If the symptoms of the disease involved the face or skull the gene implicated in the disease became a candidate for those facial traits.

This approach works because although Shriver looked at genes implicated in disease, those same genes in a healthy person may also influence the same physical trait -- length, width, shape, size -- but within the range normal for healthy individuals. Facial traits vary among humans, but do tend to group by population. For example, in general, West Africans have wider faces than Europeans and Europeans have longer faces than West Africans.

"There is a strong relationship between genetic ancestry and facial traits," said Shriver. "Using individuals of combined ancestry, European and African, we can see how the target genes alter facial traits," he told attendees at the 2009 Annual Meeting of the American Association for the Advancement of Science.

The researchers looked at a combined sample of African Americans with West African and European ancestry whose genetic makeup was known through DNA testing. To make it simpler, anyone with Native American ancestry was eliminated so that only two genetic pools were represented -- West African and European. The researchers reported on a sample of 254 individuals using three-dimensional imaging and measured the distances between specific portions of the face. Each individual had provided a DNA sample.

"We started with 22 landmarks on the faces that could be accurately located in all the images," said Shriver.

These landmarks might be the tip of the nose, the tip of the chin, the outer corner of the eye or other repeatable locations. They then recorded the distances between all the points in all directions, so they had a distance map of each of the faces.

From their DNA profiles, Shriver could determine the admixture percentages of each individual, how much of their genetic make up came from each group. He could then compare the genetically determined admixture to the facial feature differences and determine the relative differences from the parental populations.

"This type of study, done on admixed populations shows that each person is a composite of their ancestors and that the range of facial features is a continuum," says Shriver.

Shriver found that there was a very strong statistical correlation between the amounts of admixture and the facial traits.

"We chose to look at African Americans because they were a large enough and available admixed population," said Shriver. "We are trying to solidify our understanding of the origins of humans and the evolutionary processes. Looking at admixed populations shows us the influence genes have and how they relate to physical features."

A'ndrea Elyse Messer | EurekAlert!
Further information:
http://www.psu.edu

More articles from Life Sciences:

nachricht Decoding the genome's cryptic language
27.02.2017 | University of California - San Diego

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

All articles from Life Sciences >>>

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

Cells adapt ultra-rapidly to zero gravity

28.02.2017 | Health and Medicine

An Atom Trap for Water Dating

28.02.2017 | Earth Sciences

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>