We leave genetic traces of ourselves wherever we go -- in a strand of hair left on the subway or in saliva on the side of a glass at a cafe . So you may want to think twice the next time you spit out your gum or drop a cigarette butt in public . New York artist Heather Dewey-Hagborg might pick it up , extract the DNA and create a 3-D face that could look like you . Her project , `` Stranger Visions , '' fashions portrait sculptures from bits of genetic material collected in public places . `` The idea for the project came from this fascination with a single hair , '' Dewey-Hagborg told CNN . `` This turned into a research project for me exploring exactly what I could discover about someone from an artifact they left behind . '' As it turns out , she could discover a whole lot . Her process starts with finding a sample in a public place -- a strand of hair , a cigarette butt or a chewed piece of gum -- anything that might contain cells from a person 's body . `` You want something that is relatively fresh , '' she said . `` Nothing that has been stepped on or that looks like it 's been sitting around for ages . '' Dewey-Hagborg takes the sample to a community biotechnology lab in Brooklyn called Genspace . There she uses a standard DNA extraction protocol to mine the DNA , purify it and use it in polymerase chain reactions . The technical process is outlined on her blog . `` From a cigarette butt , I can learn where someone 's ancestors likely came from , their gender , eye color , hair color , complexion , freckles , their tendency to be overweight and a handful of dimensions of the face as well with a certain likelihood , '' she said . Once she obtains the sequencing information , she takes the traits she 's gathered from the individual 's DNA and feeds it into a computer program to generate a 3-D model of a face . `` The way that I use code is a lot like how a sketch artist would use a pencil , '' she said . `` I 'll take the code , and then I 'll generate different versions of a face . I 'll use the code to enhance certain facial features or decrease them based on what I find in the DNA . '' It takes about eight hours to print one of Dewey-Hagborg 's faces in 3-D at NYU 's Advanced Media Studio . Once it 's printed in what looks like a block of powder , the face is dug out , baked and hardened with a superglue-like substance . But there are limitations . The faces are not exact replicas of the stranger who left the DNA behind . Dewey-Hagborg considers it more of a family resemblance . `` It 's important to understand that these portraits are a general likeness . They 're not exact reconstructions , '' she said . `` They 'll have things in common with the person , but they wo n't look exactly like the person . '' She is also unable to determine ages from the DNA samples . So all of her faces look around 30 . Dewey-Hagborg started the `` Stranger Visions '' project with her own self-portrait about two years ago . `` Even though I was the one developing the code and training the system , I was n't really sure how much it would end up looking like me , '' she said . `` I was particularly impressed with how much the overall facial shape resembled me . '' Reaction to the project has been mostly positive , although some observers feel her work raises thorny ethical questions . `` This is very creepy , '' wrote a commenter on a Smithsonian blog post . `` We need to pursue our privacy post haste , if this is what is available to the public . '' Dewey-Hagborg said she understands that some people could be put off by the portraits or consider them an intrusion of privacy . But that 's also the point . She wants her work to raise questions about genetic surveillance and privacy issues . `` If people find it to be a little creepy , that 's OK , '' she said . `` It 's meant to make you aware of these issues and make you aware that this is possible . '' After all , `` Stranger Visions '' is an art project . And most conceptual art produces more questions than answers . `` It 's meant to be an exploration at the intersection of art and technology and science , '' she said . `` And it 's meant to be a provocation . ''
Heather Dewey-Hagborg extracts DNA from material and turns that into 3-D faces . The researchers used a technique called "reverse genetics," which uses the same genetic code as in traditional genome sequencing to create new organisms with different characteristics than their parents. `` From a cigarette butt , I can learn where someone 's ancestors likely came from ... '' she says .