Genetic detective: how to find the culprit, knowing his roots by DNA

© Illustration RIA Novosti . A. Polyanina figure overlay real genetic maps (median network of haplotypes of N1b indigenous peoples of southern Siberia) on a map of the worldGenetic detective: how to find the culprit, knowing his roots by DNA© Illustration RIA Novosti . A. Polyanina

He came in the house to the young girls, was presented by public utilities and committed rape. The girls were so scared that he could not describe the stranger. This went on for years. From one district of Novosibirsk, some of the other parents called the police and tearfully told me about the thugs who came under the guise of harmless hardworking. However, all ended two weeks after investigators asked the Institute of medical genetics SB RAMS (Tomsk) with the question of the origin of DNA.

What do DNA it is possible to calculate the origin? It appears, however: a long history of this Russian genetics. In several institutions of Russia conducting research related to the study of the characteristics of the individual, which are «hardwired» in the genome of certain people. The distribution of these features can be applied on a geographic map.

What is the basis for these studies?

Says academician of RAS, scientific Director of the Institute of General genetics RAS, Nicholas Jankowski: «I was in the history of mankind, a period when all people lived in one place, and then there was the resettlement. Gradually mastering space, people have left a genetic trail. The last such settlement occurred less than 100,000 years ago, and it turns out that knowing the sequence of occurrence of mutations in time and in geographical space, we can map the distribution of genetic mutations. The starting point on this map is the occurrence of mutations, since some mutations deposited in the place where they went.»

The task of creating this card were decided by the topology (topology is a branch of mathematics that studies very General phenomenon of continuity), theoretical physicists and chemists, and then genetics.

It turns out that knowing the sequence of accumulation of mutations in time and space, scientists, in fact, know the rules of the game «genetic quest», and this «action» can not only open the eyes of the historians on the flow of migration, but also to give to the investigators the key to the origin of a particular person.

CSU used a genetic tree from the other end, «pulling» a Y chromosome from the biological sample of the rapist. The DNA fragment of the thirty millions of letters were found those that indicated belonging to a particular district of Siberia, namely the Western Buryatia.

© N. Yankovskiy illustration shows the work undertaken for building a map of origin of the perpetrator from NovosibirskGenetic detective: how to find the culprit, knowing his roots by DNA© N.Yankovskiy illustration shows the work undertaken for building a map of origin of the perpetrator from Novosibirsk
«Investigators from Novosibirsk for a long time trying to work on the sketch, says Nicholas Jankowski, but the image on the descriptions of the girls were not accurately compiled. The sketch came out that the roots of the rapist most likely was pointing to the North Caucasus. And when it came to our colleagues in Tomsk, it turned out that the instructions to the North Caucasus in the DNA do exist, but the maximum concentration of the genetic characteristics of the rapist are in the West of Buryatia. How much in Novosibirsk, Buryat, and Western? Bit. So two weeks later, the rapist was found.»

The centre of the mutations were in the Barguzin district of Buryatia Republic. With these data converge and lines of inquiry. With the help of cellular companies, it was found that the phone had been used near the places of crimes in the hours when the rapist came to the victims. The rooms chose a pattern and went to the resident of the Barguzin district. He had taken a saliva sample, which coincided with the DNA of the criminal. It turned out that the offender is the father of two children, a former teacher, school physical education teacher. However, in life you can change almost everything. In addition to the DNA.