Have you ever spotted someone in a crowd who you thought was a friend, only to realize it’s just someone who looks remarkably like you?
Many of us have seen so-called doppelgangers of loved ones, family members, and even ourselves.
Now, a study has found that these doppelgangers not only look alike — they also likely share very similar DNA and even share personality traits.
Researchers at the Josep Carreras Leukemia Research Institute in Barcelona have found that strong facial resemblance is linked to shared genetic variants.
“These findings will have future implications for forensic medicine – reconstructing the criminal’s face from DNA – and for genetic diagnostics – the photograph of the patient’s face already gives you clues as to what genome he or she has,” said Dr. Manel Esteller, senior author of the study.
A study found that doppelgangers don’t just look alike — they also likely share very similar DNA and even share personality traits. Pictured: Michael Malone (left) and Charles Hall Chasen (right)
For the study, the team recruited 32 matched couples who were photographed by Francois Brunelle, a Canadian artist who has been photographing lookalikes since 1999. Pictured: Pedro Lopez Soto (left) and Albert Pueyo Kaotico (right)
There’s a one in a trillion chance of finding your doppelganger
In 2015, researchers revealed that the chance of finding your double is one in a trillion.
Teghan Lucas, a student at the University of Adelaide, conducted the study using a large database of face and body measurements from nearly 4,000 people combined with mathematical equations.
She discovered that by using a combination of eight facial features, the probability of finding two faces with the same measurements in the general population was less than one in a trillion.
Amid the expansion of the World Wide Web, the number of people identified online as “virtual twins” or “doubles” has exploded.
In their new study, the team set out to characterize these random pairs, who objectively share facial features, at the molecular level.
For the study, the team recruited 32 matched couples who were photographed by Francois Brunelle, a Canadian artist who has been shooting lookalikes since 1999.
The researchers used three different facial recognition algorithms to determine an objective measure of how similar the pairs were.
Participants also filled out lifestyle questionnaires and provided saliva samples for DNA analysis.
“This unique set of samples has enabled us to investigate how genomics, epigenomics and microbiomics can contribute to human similarity,” says Dr. Eteller.
The results showed that the lookalike pairs had similar genetic makeups, or “genotypes.”
However, they differed in DNA methylation (the regulation of gene expression) and microbiome landscapes (communities of bacteria, viruses and fungi).
Physical traits, such as weight and height, and behavioral traits, such as smoking and education, were found to correlate between the lookalikes.
This suggests that a shared genetic variation is not only related to a similar physical appearance, but can also influence shared behaviors and habits.
“Our study offers a rare insight into human similarity, showing that people with extremely similar faces share genotypes while mismatching at the epigenome and microbiome level,” explained Dr. Eteller.
The researchers highlight several limitations of the study, including the small sample size, the use of 2D black-and-white images, and the lack of diversity among participants.
The results showed that the lookalike pairs had similar genetic makeups, or “genotypes.” Pictured: Stella Cappiello (left) and Nunzia Girardi (right)
Physical traits, such as weight and height, and behavioral traits, such as smoking and education, were found to correlate between the lookalikes. Pictured: Ana Maria Sanchez (left) and Katherine Romero (right)
However, they hope that the results could prove useful for future studies in biomedicine, evolution and even forensics.
dr Esteller concluded, “Through a collaborative effort, the ultimate challenge would be to predict human facial structure based on the individual’s multiomics landscape.”
The study comes shortly after researchers found the chance of finding your doppelganger is one in a trillion.
Teghan Lucas, a PhD student at the University of Adelaide School of Medicine, conducted the study using a large database of face and body measurements from nearly 4,000 people combined with mathematical equations.
She discovered that by using a combination of eight facial features, the probability of finding two faces with the same measurements in the general population was less than one in a trillion.