The proverb says: He who is similar takes it. Folk wisdom tries to explain the law of attraction among people on the basis of physiognomy. But the science goes further than that: Thanks to use Algorithms From facial recognition, strong facial similarity can be associated with shared genetic variants. This, at least, is what emerged from a study published in Cell Reports by a group of researchers led by Manil Esteler From the Josep Carreras Institute for Leukemia Research in Barcelona. Our study – explains Esteller – provides rare insight into human similarity, and shows that people with very similar faces they share genotypes common, while it is discordant at the level epigenome And the microbiome
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Characterization of the human at the molecular level

The number of people identified online as Virtual twins or doubles which are genetically unrelated due to the expansion of world wide web And the possibility of sharing photos of humans all over the planet. In the new studio, Esteller and his team decided that Describe, at the molecular level, randomly selected people who objectively share facial features.

To do this, they recruited human likenesses from the photography business of Francois Brunel, A Canadian artist who has been getting lookalikes all over the world since 1999. They’ve got them Face photo of 32 similar couples. The researchers identified an objective measure of similarity between couples using Three different algorithms for facial recognition. Additionally, participants completed a Biometrics and lifestyle survey complete and submitted
DNA saliva for multitomics analysis. This unique set of samples allowed us to study how genomics, epigenetics, and microbiomes might contribute to human resemblance, Esteller says.

Half of the couples examined also have similar habits and behaviour

In general, the results revealed that These individuals share similar genotypes, but differ in the methylation (epigenetic modification) of DNA and in the microbiome landscape. Half of the similar pairs were placed in the same group by the three algorithms. Genetic analysis revealed that 9 of these 16 pairs assembledbased on 19,277 common single nucleotide polymorphisms.

In addition to, Physical traits such as weight and height, as well as behavioral traits such as smoking and education, have been linked in similar pairs. taken together, The results suggest that shared genetic variation not only affects similar physical appearance, but may also influence common habits and behaviors.. “We’ve provided unique insight into the molecular traits that potentially influence the construction of the human face,” Esteler says.

The limits of the study

However, the study has some limitations, as the authors themselves admit: The sample examined was small, black and white 2D images were used, and most of the participants were Europeans. However, the results could provide a molecular basis for future applications in various fields such as Biomedicine, evolution and forensics.

These findings will have future implications in forensics, in reconstructing a criminal’s face from DNA, and in genetic diagnosis: an image of a patient’s face will already provide clues to the genome he has, Esteller says. Through collaborative efforts, the ultimate challenge will be Predict the structure of the human face based on the individual’s multiple panorama.

Facial features are greatly affected by the environment

But Really, people with similar faces might have similar DNA? In a sense, yes – he answers Gian Gaetano Tartaglia IIT researcher and head of the RNA Systems Biology laboratory -. Facial features are greatly influenced by the environment. People with similar faces often have a common genetic background. This is because living in a certain environment, for example at the North Pole or the equator, leads us to get a certain cut in the eyes, skin color, tendency to baldness, etc. Basically we have to take into account that Expression of genes (Any number of copies Rna which produces a cell of a specific gene) that determines tissue growth, and It is very likely that people with the same mutations, or SNPs, may have a similar oval face shape, or a similar nose.….

Research leadership, but with reservations

How reliable is such a study? Definitely a “pioneering” study because Associate an external characteristic such as appearance with something internal such as DNA. There is a slightly frustrating question: Photos of similar couples, originally collected from men, are recognized by algorithms only in 50% of cases.

This means that our ability to be physiologists is not entirely objective, or at least categorizes men differently than computers. Perhaps we should also consider that algorithms are not perfect. So the ability to find similarities, all of humanity, is difficult to measure (and thus, also, DNA similarity cannot be easily checked), says the expert.

The limit of belonging to the same ethnic group

What are the weaknesses in addition to those highlighted by the authors? It is easy to find similarities in the same population, and this is the weakest point: the multiplier is the individual who comes from the same ethnic group. The fact that my version is racially similar Helps in making lifestyle statistics (smoking, drinking, longevity, etc.), But it is currently not useful to find more detailed information (Cancer, neurodegeneration, etc.). In other words, classification is neither accurate nor effective for the development of other aspects, such as preventive medicine, that is ongoing.

Let’s see it from a more detailed point of view. Our children are similar to us because they have the same mutations, or SNPs. Many mutations or polymorphisms occur not only in the family, but also in the population where the ethnic group lives (a kind of “super family”). For this reason, the ethnic groups who were isolated and who did not travel to other places are well defined, even morphologically. The similarity between those who live in the same environment is emphatic.

The classic example is thatSickle cell anemia It is abundant in Sardinia. Interestingly, neither the epigenome (that is, chemically modified DNA) and bacterial populations could be used to classify similar individuals, suggesting that a significant level of complexity is due to the environment. We know that bacteria They have a significant influence on the development of some diseases (Let’s think of bacteria Helicobacter pylori and the stomach cancer for example), so categorization is really hard.

Precision medicine on the fly

And what could be the potential scientific ramifications, the benefits to people as well as the risks that relying on algorithms could cause in such a sensitive field? Being able to measure genetic characteristics based on appearance has always been a dream. The biggest benefit would be to accurately make some kind of “quick” medicine, Collect common characteristics between individuals through algorithms. Knowing if an individual has heart disease can for example prevent their duplication (Prostate cancer, etc.) … Various attempts have been made in the past Connect the common characteristics of individualsIt is enough to recall Cesar Lombroso and classify criminals based on the shape of the skull, but now the measurement of football is more objective. It will become more accurate as the abundance of collected genome samples increases.

The cultural side of it scares me a little bit. Part of the article states that similar people also have the same educational background. It is dangerous to think that people are predetermined in their studies based on physical characteristics. Social aspects, that is, interactions between individuals, especially families (but not only) influence our choices every day. We can’t talk about preselection.