Doppelgangers Don’t Just Look Alike, They Act Alike and Share DNA


Francois Brunelle’s photo project on doppelgangers inspired a team of researchers to study the lookalikes and discovered that it is not just facial similarities they have in common.

After viewing Brunelle’s incredible photos, a team of geneticists from the Leukemia Researching Institute in Spain investigated 32 doppelganger couples and found that they also have similar DNA and behaviors.

In fact, half of the doppelganger couples were found to be more like identical twins with comparable genotypes, a DNA sequence each individual has.


The scientists, led by Dr. Manel Esteller, also found that the doppelgangers have similar height and weight and even shared the same habits such as smoking and education.

Brunelle tells PetaPixel that Dr. Esteller reached out to him after seeing a New York Times article in 2014 about his project I’m not a look-alike!.

“[I felt] very good [when they made contact],” Brunelle says. “Out of curiosity, to know more about the look-alikes and to participate in something much bigger than my humble project.”

Brunelle met Dr. Esteller in Madrid and Barcelona and the team reached out to people who had been caught through Brunelle’s lens.

Doppelganger Study

The researchers used facial recognition algorithms, lifestyle questionnaires, and DNA swabs in their method.

They used three different facial recognition algorithms to determine an objective measure of likeness for the pairs. They used several programs because each system can provide variable results, so the more outcomes the better the conclusion will be.

Participants completed questionnaires about their lifestyles which revealed their jobs, education, and habits. They also provided saliva samples for DNA analysis.

“This unique set of samples has allowed us to study how genomics, epigenomics, and microbiomics can contribute to human resemblance,” Dr. Esteller says.


The team collected 68 biometric and lifestyle attributes from the 32 pairs, which led them to find a correlation with height, weight, and behavioral traits.

“Overall, we provided a unique insight into the molecular characteristics that potentially influence the construction of the human face,” the team wrote in the study published in Cell Reports.

‘We suggest that these same determinants correlate with both physical and behavioral attributes that constitute human beings. These findings provide a molecular basis for future applications in various fields such as biomedicine, evolution, and forensics.”


The researchers highlight several limitations of the study, including the small sample size, use of 2D black-and-white images, and lack of diversity among participants.

However, they hope the findings could prove useful for future studies across the fields of biomedicine, evolution, and even forensics.

For his part, Brunelle believes that his project is about identity and people finding themselves.


“Who am I? The person I am looking at in the mirror (what if someone else, somewhere is looking at the same person, more or less) or something else that is not related to my appearance?”

More of Brunelle’s work can be found on his website.

Image credits: All photos by Francois Brunelle.