Gene for survival

The slightest relief was enough, an extra ration of bread, a plate of nettle soup, so that the soul, squeezed to the utmost, would wake up. And then with unprecedented enthusiasm and reverence, simple joys were appreciated: dry clean asphalt, window frame with whole glass, a wall heated by the sun, green trees, they were not as green as that spring! A bed with clean sheets was also a miracle, and a flower that could not tear, chew, cook a salad from it, but leave it just a flower that grew on the lawn.
Ales Adamovich, Daniel Granin “The Blockade Book”

The Siege of Leningrad is the longest siege of the city in the history of the 20th century. Live blockade - those who were able to endure hunger. How did they manage to do this from a biological point of view, and how are they unbiased in answering the question posed?

Surrounded but not taken

The siege of Leningrad lasted 872 days. On June 22, 1941, the war began, on September 8, Leningrad was surrounded by Army Group North, the combined forces of the Wehrmacht, and from the north by Finnish troops. So began the siege of the city. In fact, the railway communication was interrupted at the end of August. At the beginning of the siege, the Badayev warehouses, large food warehouses of Leningrad, were destroyed. The directive of the opponents was to destroy the city, to freeze its inhabitants.
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First winter

Since November 1941, the most terrible pages in his memoirs began. On November 21, the heating system was turned off, and the water supply system failed on December 6 With the arrival of winter in the city came hunger. And with him - the loss of consciousness from hunger, death from exhaustion, murder for the cards and cases of cannibalism. The size of the daily food ration for workers at the end of October was 250 grams of bread per day, the military - more servants, children and the elderly - less. In order to fill the missing ingredients in the recipe for blockade bread included wallpaper paste and food pulp.

Value

Leningrad survived the first winter, and with it the blockade. During the war, each victory raised self-consciousness. The fact that the city was under siege gave hope to those who fought at the front and in the rear. Subsequently, the blockade was awarded a memorial sign "Resident of besieged Leningrad." In accordance with the modern course of self-awareness and patriotism, the blockade of Leningrad is perceived as a great feat. In order to engage in research of great exploits, you need to have an interesting hypothesis, a well-thought experiment and reliable results.

Research results

In accordance with an article published in 2014, a group of scientists from St. Petersburg found out that among women who survived the blockade, those variants of genes that allow them to use energy more economically are more common. Thus, the UCP3 gene works as a transporter in the mitochondrial membrane and protects them from oxidative stress, while the PPARA gene regulates lipid metabolism in the liver. The genes of the PPAR family are associated with the risk of obesity; therefore, attention is paid to them from companies offering DNA diagnostics.

Staging experiment

The study group included 206 people who survived at least 4 months of the blockade. The control group was represented by 139 individuals over the age of 69 from a population sample of the North-West region. Within both groups, there were divisions into subgroups according to gender and age. The experiment, in fact, has already been set - cruel, cynical and terrible. The study consisted of a analysis of the results: a molecular-biological analysis of 5 genes related to the metabolism of lipids and glucose. DNA was isolated from white blood cells taken from the blockade blood and the control group. Comparison of gene variants was performed using PCR, the results were processed statistically. For more accurate processing, the “experimental” group and the control group were divided into subgroups, depending on gender and age.

Hungry winters in science

Prior to this, a series of studies was carried out in the States, examining the impact of the hungry winter of 44-45 years in the Netherlands on children bred that winter. The conditions of the experiment were similar, by the end of the war in the country the stocks of food had simply run out. For comparison, the total sample was 3,307 people in the experimental group. The number of the control sample, people whose mothers did not suffer from hunger, is indicated implicitly. The authors say that they selected controls so that the number of births per month coincided in both samples.

Criteria of science

At the end of the article, a neat conclusion was made that the research requires an extension of the sample. However, the current result really raises questions. The initial hypothesis was that all people from the experimental sample underwent stress for at least 4 months. At the same time, it is not known exactly how the blockade took place for individuals. It is not clear how ethical it is to ask the subject: “Have you really suffered? How long? ”When making the sample in the biobank. On the other hand, the formulation of a similar task in the sociocultural context of our country requires that the solution be finding something special. The results given in the article raise questions. From a scientific point of view, such issues can be resolved with a repeated experiment, which, of course, is out of the question.

View from the outside

Stephen O'Brien, head of the Dobzhansky genomic bioinformatics center, notes that the study, which attracts attention and is provocative, does not show any stunning results. It is rather a good start for a long hard work. Valery Ilyinsky, head of the Genotek Moscow Medical Genetics Center, believes that from a methodological point of view, the work does not raise questions, but it has serious shortcomings that do not allow the conclusions to be regarded as final or at least somewhat significant. “The disadvantages include an extremely modest sample size, as well as a small number of genetic markers that were investigated. There are several tens of millions of genetic markers that are found in humans. Hundreds and thousands of markers are responsible for many signs, and the role of each is usually small. To conduct such a study requires the participation of several thousand people to achieve the statistical significance of the results, ”- commented Valery.

Flies as a metaphor

The study mentions such key words as aging, longevity, survival, and there is also a link to an important historical moment in the history of Russia. In order to understand the significance of the study, you can try to mentally transfer the study from people to flies. Not to show disrespect for the heroes and victims of the Great Patriotic War, but to understand the scale of the conclusions. Fundamental patterns of aging and longevity may coincide not only within a species or genus, but also on larger taxonomic scales. Drosophila melanogaster is one of the most popular model organisms. So, an article could be published stating that “scientists have found longevity genes in 206 flies,” however, it would have been perceived more than skeptically.

Inconvenient questions

Of course, there are trends in science. Cancer, aging, genomic technologies are interesting topics for many that are financed better than, say, coral diseases, salivation, polymerase chain reaction. However, there is a context, something outside of science. In Russia, it is related to the Great Patriotic War. The thoughtful design of the experiment allows you to receive facts that are not distorted by the pressure of society, insufficient sampling, and personal preferences. The creation of biobanks and accurate collection of information contribute to the movement towards personalized medicine. Even complex questions can be answered, but not immediately.

This is the first material from Genotek. We are engaged in genetic research. This is a modern technology that allows you to look at yourself from a new perspective. One of our possibilities is to uncover your genealogy by DNA pattern. At Geektimes, we recall famous stories with new details that it became possible to read in DNA. For example, that the entire population of the Earth comes from one group of immigrants from Africa, how the Europeans acquired white skin, what mixture the population of Japan consists of and how the study of national folklore helps in the study of migrations and resettlements. Read us.