Inspired by his discovery of his look-alike, the English actor Rowan Atkinson, and François Brunelle, a Canadian artist and photographer, began recording look-alikes in a picture series called “I’m not a look-alike!” in 1999.
The project was a huge success on social media and other parts of the internet, but it also grabbed the attention of geneticists.
Manel Esteller of the Josep Carreras Leukaemia Research Institute in Barcelona, Spain, in particular.
Esteller had previously examined the physical distinctions between identical twins, and he wanted to investigate the opposite: people who appear alike but aren’t related. “What’s the deal with these people?” he pondered.
Esteller and his colleagues set out to classify strangers with objectively similar face traits on a molecular level. To do so, they used human duplicates from Brunelle’s photography. Using three distinct facial recognition algorithms, the team acquired headshot images of 32 lookalike couples and derived an objective measure of resemblance for the pairs.
“Our findings provide a unique perspective into human likeness by demonstrating that persons with extreme lookalike faces share common genotypes but differ at the epigenome and microbiome levels. Genomics groups them together, whereas the rest distinguishes them “According to Esteller’s remark.
The findings were published in Cell Reports.
They were brought together through genetics.
In addition, the subjects completed a detailed biometric and lifestyle questionnaire and contributed saliva DNA for multi-omics analysis. “We’ve been able to explore how genomes, epigenomics, and microbiomics can contribute to human similarity thanks to this unique combination of samples,” Esteller added.
The findings show that these people have comparable genotypes but differ in their DNA methylation and microbial environments. Half of the lookalike couples were clustered together by all three techniques. Based on 19,277 common single-nucleotide polymorphisms, genetic research revealed that nine of these 16 couples clustered together.
“These people look alike because they share key elements of their genome or DNA sequence,” Esteller explained to The New York Times. That person who look more alike have more genes in common “seems like plain sense, but has never been demonstrated,” he adds.
Physical characteristics such as weight and height, as well as behavioral characteristics such as smoking and education, were found to be connected in lookalike pairings. The findings indicate that “shared genetic variation not only corresponds to comparable physical appearance but may also influence common habits and behavior.”
The research could one day help forensic science.
“We gave a unique look into the molecular traits that may influence human face formation,” Esteller added. “We propose that these same variables correspond with both physical and behavioral characteristics that define humans.”
A few study drawbacks included the small sample size, the use of 2D black-and-white photographs, and the fact that the bulk of the cohort consisted of European people. Despite this, the findings may provide a molecular foundation for future applications in healthcare, evolution, and forensics.
“These findings will have future ramifications in forensic medicine—reconstructing the criminal’s face from DNA—as well as in genetic diagnosis—the photo of the patient’s face will already offer you hints as to which genome he or she has,” Esteller added. “The ultimate objective would be to forecast the human face structure based on the individual’s multi-omics landscape through joint efforts.”