Dactyloscopy is ... Genetic fingerprinting

One way or another a person leaves his mark wherever it happens: skin particles, hair, saliva. And yet the cells of the epidermis constantly, albeit in small amounts, secrete a secret: sweat and fat. It is at their expense that fingerprints appear on all affected subjects. And their drawing is unique for every person. So, where to make a fingerprint, and why this can come in handy?

Essence

Dactyloscopy is a science that studies papillary patterns, that is, those dashes on the skin that every person has at his fingertips. In addition, the so-called identification process on the imprints of these lines. The fact is that they are unique for every person and remain on everything that a person touches. That's why this is a great method of identifying a person, simple enough and effective to be used around the world.

Historical digression

Initially, the concept of fingerprinting as a section of trasology was suggested by Argentine physician F. Latzina in 1894. Until then, the term "iknaphalangometry" was not quite successful. Then the method of fingerprinting and their use in forensic science experienced a real boom. The scientific basis for this was given by the famous English explorer Francis Galton, and his idea was developed and firstly widely implemented in practice by Juan Vuchetich. He developed a classification of prints, and later - a special fingerprint registration system in some South American countries. So it became possible to identify people in the wake of papillary drawings - one of the main tools of modern criminalistics.

It is difficult to say which of the scientists mentioned gave the greatest impetus to such a science as dactyloscopy. This is a question that often causes much controversy, since Galton proved that mathematics are impossible mathematically impossible for different people, and Vuchetich seriously eased the very problem of identification. Most likely, in fact the main role was played by a combination of these achievements.

Genetic fingerprinting

If the usual is understood as fingerprinting, then what is used here? Obviously, DNA analysis. This is a much finer and more accurate instrument. If the usual fingerprinting can tolerate some error, then errors are virtually eliminated, since each person's DNA is unique. The genotyping method was developed in 1984 by a group of scientists led by Alex Jeffreess. He gained fame, as he was used in some scandalous criminal cases, as well as in an incident involving the football player OJ Simpson in 1995.

Methodology

This way of identifying a person became possible due to the special structure of human DNA. The fact is that approximately 95% of the molecules are non-coding, that is, they do not carry genetic information, but contain repetitive sequences that can be scattered far apart or nearby. It is in the latter case that they are called satellites. The number of repetitions in them can be very different, and if you take different people, it is guaranteed not to coincide.

There are also clusters in which the number of sequences is very small - they are called mini satellites. And in a specific place in DNA, each person has two such structures, one from each parent. Genetic fingerprinting is an analysis of these mini satellites. Thanks to it, it is possible to identify the identity of the DNA with high enough accuracy. And today this technique plays the same role as fingerprints once. But if the last criminal can be discreetly erased, then there is practically no physical traces of his stay, that is, particles of skin, blood, saliva, hair, etc., is practically impossible.

Accuracy

Genetic fingerprinting is distinguished by a sufficiently high reliability, that is, if certain standards are complied with, several test results obtained by different laboratories will not differ. The development of certain rules, common to all studies of this type, is now just working.

As for accuracy, the probability of coincidence of the analyzed DNA parts in different people is vanishingly small. It is worth saying that the chances for this are higher, if we are talking about close relatives, their results will in any case be similar. In addition, the quality of the material has a significant influence on the accuracy of genotyping. It's one thing to go through fingerprinting, that is, to pass the analysis voluntarily, and quite another to try to extract DNA from droplets of dried blood or saliva.

Modern application

There is a small range of situations in which such a procedure can be useful. First of all, this is a crime area. The suspect's guilt can be proved, for example, if parts of the skin under the fingernails of the victim are found, by DNA coinciding with it. For forensic experts, genetic fingerprinting is a real find that helps identify the identity of the offender.

A number of other situations that require the compilation of DNA profiles are disputes about paternity and inheritance. In the last few decades, these analyzes have become quite accessible and popular.

Among other things, genotyping is used by anthropologists to trace the history and interconnection of various peoples. Thanks to the analysis of the DNA of modern people , curious discoveries and assumptions were made.

Finally, this technique is used in livestock breeding to confirm the purity of the breed or control genetic diversity.

Where and how to do it?

Fingerprinting is easy. This is a very simple and absolutely painless procedure. To begin with, the fingers are covered with a special dye, and then they make prints on paper. However, in many institutions simply computer scanning of papillary patterns is carried out - this allows you to get rid of the difficulties of subsequent digitization.

From 2015 to pass this procedure is necessary when receiving a new generation of foreign passports in Russia. In addition, when submitting an application, for example, to a British visa, it is also necessary to hand over fingerprints. But you can do this voluntarily - just contact the nearest FMS office.

If there is a question about where to go through fingerprinting of DNA, then the way lies in specialized medical organizations. As the cost of this test declines and the distribution of equipment necessary for its carrying out, such institutions become more and more numerous. This is, for example, the Center for Molecular Genetics, where the result can be obtained during the working week for 10-20 thousand rubles, or the Institute of Medical Genetics, where this analysis will cost about the same amount. The material, as a rule, is blood or buccal epithelium (a smear that is taken from the inside of the cheek). Obviously, this procedure is also harmless and almost painless.

Ethical issues

A number of lawyers believe that the creation of a system containing fingerprints or the gene material of not only criminals but also ordinary law-abiding citizens contradicts basic human rights when it comes to forcing them to undergo these procedures. The main reason for concern is the possible hacking of a single database, which will entail unauthorized access to confidential information, because genetic fingerprinting is actually a DNA passport, and such information should not simply be publicly available.

In addition, the collection and constant updating of such a database is a very expensive pleasure, and costs, obviously, will fall on the shoulders of taxpayers. As the world and Russian practice shows, it makes sense to limit the circle of persons for whom fingerprinting becomes obligatory, military, security forces, civil servants and, of course, convicted or serving administrative arrest. For others, the procedure for fingerprinting or the delivery of gene material must be strictly voluntary.