1892 English anthropologist Franz Galton He proposed 40 distinctive features to classify fingerprints. footprints are so different from each otherI would estimate that the odds of two people having the same thing is 1 in 64 billion, a number far exceeding the world’s population.
In other words, it turns out It is almost impossible to find two people with the same fingerprints. And this happens because many factors intervene in its formation while we are in the womb. In particular, the tiny bumps and ridges found on human fingertips begin to form around the 13th week of life of the fetus.
It is almost impossible to find two people with the same fingerprints
The skin is thus exposed to intrauterine pressure, movements and position of the fetus in the uterus, nutrition, blood pressure, amniotic fluid, etc. The smallest deviation from one of these random factors leads to Changes in the overall structure of the fingerprint. From then on, the resulting drawing will be immutable, always the same and forever, until death.
Photo: Mustafa Sen/IStock
Fingerprints of the twin brothers
Not even those of identical twin brotherswho are genetically perfect clones share the same fingerprints. In addition to the environmental stresses mentioned above, each twin has experienced their own genetic mutations in the womb, which also appear to influence the formation of fingerprint patterns.
This is what researchers at the University of Edinburgh say, using human cell models in the laboratory and later mouse models (mice don’t have fingerprints like we do, but they do have transverse ridges of skin on their fingers that develop similarly).
Their conclusion is that the molecular signaling pathways that exchange information and instructions between genes are very diverse sensitive to tiny local factors within the uterus. In both humans and mice, the Wnt pathways (the ones that form the grip of our fingers) seemed to stimulate the growth of ridges on the finger’s outer layer of skin; The BMP ways (bone morphogenetic protein) suppressed the formation of these grooves; and the Sewage Treatment Plant Roads (ectodysplasin A receptors) helped shape the size and spacing of the skin ridges.
Turing and the zebras
When the activity of the WWTP pathways was silenced in mouse models, their fingers did not display transverse ribs, but rather a mole-like pattern. Consequently, it was concluded that the pushing and pulling in burr formation reflects patterns emerging from what is known as Reaction-diffusion systems with Turing instabilities.
A Turing pattern is a mathematical concept developed by Alan Turing in 1952 to explain how stripes and spots in nature have small random differences in their structure. Something that, for example has been seen in the stripe patterns of zebraswhich are also different from each other.
In summary, the study suggests that the forces that give each human fingerprint an individual uniqueness they are the same ones that underlie many other spots in nature, such as e.g. B. Crosswalks. They are the forces of the environment intertwined with the random component of genetics, which in turn is fed back from the environment. This makes us all have a common origin while certainly being different from each other.