Via Tech Times
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Virtual 3D faces can now be produced from DNA code. The application,
developed by Mark Shriver of Pennsylvania State University, produces a
virtual mug shot of potential criminals. Pictured here is a work flow
diagram showing how facial features were processed for the application.
(Photo : PLOS ONE)
Models of a criminal's face may so be generated from any trace of DNA
left at the scene of a crime. Computer-generated 3D maps will show
exactly how the suspect would have looked from an angle.
Mark Shriver of Pennsylvania State University and his team developed
the application, which produces a virtual mug shot of potential
criminals.
Shriver and his team took 3D images of almost 600 volunteers, coming
from a wide range of racial and ethnic groups. They superimposed more
than 7,000 digital points of reference on the facial features and
recorded the exact position of each of those markers. These grids were
used to measure how the facial features of a subject differ from the
norm. For instance, they would quantify the distance between the eyes of
a subject, and record how much more narrow or wide they were than
average.
A computer model was created to see how facial features were affected
by sex, genes and race. Each of the study participants were tested for
76 genetic variants that cause facial mutations. Once corrected for
race and sex, 20 genes with 24 variants appeared to reliably predict
facial shape.
"Results on a set of 20 genes showing significant effects on facial
features provide support for this approach as a novel means to identify
genes affecting normal-range facial features and for approximating the
appearance of a face from genetic markers," the researchers wrote in the article announcing the results.
As part of data collection, the team asked participants to rate faces based on perceived ethnicity, as well as gender.
Digital facial reconstructions from DNA have proven to be notoriously
unreliable. Even seemingly simple information like height can be
difficult to determine through genetic analysis. Other aspects of human
physiology, such as eye color, are easier to predict using genetic
analysis.
"One thing we're certain of [is] there's no single gene that suddenly
makes your nose big or small," Kun Tang, from the Shanghai Institutes
for Biological Sciences in China, said.
In order to further refine the system, Shriver has already started
sampling more people. Adding further diversity to the database should
allow the application to make even more accurate recreations of a
person's face. In the next round of testing, 30,000 different points
will be used instead of 7,000. Merging this development with 3D
printers would make it possible to print out 3D models of a person, just based on a piece of DNA.
Such models - digital or physical - are not likely to be used in
courts anytime soon. A more likely scenario is use as modern day version
of police sketches, assisting police in finding suspects. Only after an
arrest would the DNA of a suspect be compared to that collected at the
scene of a crime.
Creating 3D facial models from genetic evidence was detailed in Nature.