Identical twins have the same set of genes. But for some reason, one does not get out of the disease, and the other never sneezed. It turns out that our health depends not only on what we inherit from our parents, but also on other factors? The science of epigenetics has proven that a person can change what is written for him, that is, his DNA. In what way?
If a person follows a balanced diet, he will forget about bad habits and acquire useful ones, he will not only be able to change his life program, recorded in his own DNA, but will also pass on healthy genes to his descendants, which will prolong the years of children and grandchildren.
Garlic turns on the genes
The first and foremost is food. In principle, each of the products can affect the work of genes. But there are some, the usefulness of which scientists have already proven 100 percent.
Among them - green tea. Green tea contains catechins (epigallocatechin-3-gallate, epicatechin, epicatechin-3-gallate, epigallocatechin), which can suppress cancer-causing genes and activate those genes that can fight tumors. Drinking 2-3 small cups of green tea every day is enough to keep your DNA in anti-cancer combat readiness. Green tea is especially useful for women, among whose relatives there are patients with breast tumors.
Another product is garlic. Other compounds work in garlic - diallyl sulfide, diallyl disulfide, diallyl trisulfide. It is necessary to eat 2-3 cloves of garlic a day to start the genes that manage not only the processes of cell death that give metastases, but also fight old age, prolong life.
The third panacea is soy. Soy contains isoflavones (genistein, daidzein) - an effective antitumor agent for breast cancer, prostate, larynx, colon and leukemia. Scientists advise using soy in dietary supplements and sticking to the dosage indicated on the packages.
The fourth fighter for healthy genes is grapes and products from it (juice and wine). A bunch of dark grapes (that's 120 g of grape juice or 100 g of dry red wine) added to your daily menu will provide the body with resveratrol, a gene-changing substance.
In a diet that will appeal to good genes, it is worth including 100 g of dark red tomatoes (substance lycopene) with the addition of olive oil. Tomatoes should be eaten four times more if there are cancer patients in the family.
Another vegetable that your heirs will remember with a kind word is broccoli (substance indole-3-carbinol). 100 g of broccoli - each, 300 g - at risk of cancer.
Be sure to eat nuts, fish, eggs and mushrooms - they provide the body with microelements selenium and zinc, which also change DNA.
The obese constitution was fixed in the genome
The work of genes depends on the diet. The diet should be low-calorie (no more than 2 thousand kcal per day). It delays the aging of a person, guarantees longevity to his children and grandchildren. Epigenetics also explains the obesity epidemic that has broken out today: we are becoming more and more full because our mothers overeat before and during pregnancy. This is confirmed by experiments conducted on animals: overfed mice each time produced even more obese offspring, and a similar constitution was fixed in the genome.
Genes like it when their master keeps himself in good shape. physical form. Scientists have determined that regular exercise for 45 days on a regular exercise bike activates about 500 genes! And if you practice regularly and further, you can change even more genes for the better.
About bad habits written-rewritten. But the influence of cigarettes, alcohol and drugs directly on genes has only recently been proven. It turns out that more than 150 sections of DNA in chronic alcoholics get abnormal activity. Result: the alcoholic cannot concentrate, does not remember anything, cannot control his emotions. But the saddest thing is that he passes on diseased genes to offspring.
And about 120 genes remain changed even 10 years after quitting cigarettes. And again, among them are the most important genes that control cell division. The result is cancer in the smoker. But there is reason for optimism: genes can be corrected, and the less experience of addiction to, the sooner this can be done.
Genes are also affected by emotions, both positive and negative, received at home, in the family, at work.
And, finally, the ecological situation in which a person lives. Obviously, industrial emissions, car exhausts, nitrates in food, polluted water also lead to breakdowns in the genes.
Do you want to live longer? Do you wish health to your children and grandchildren? Then take care of your genes.
Now you know how to do it?
Human genetic engineering still seems to us, ordinary people, something out of the realm of science fiction. All the more surprising was the report of The Telegraph, which said that the UK Council of Ethics allowed the genetic engineering of human embryos. It is clear that from the recommendations of the Ethics Council to the law on genetic interventions there is a “great distance”, but the first step seems to have been taken.
The Telegraph reached out to Professor Karen Jung, chairman of the working group on genome editing and human reproduction. Ms. Professor said that in the future, among the reproductive technologies may be the introduction of hereditary changes in the genome to ensure certain characteristics of children. At first, of course, hereditary diseases will be dealt with in this way, but then “if the technology develops successfully, it has the potential to become an alternative reproductive strategy available to parents to achieve a wider range of goals.”
When asked if genetic editing can be used to make children tall, with blond hair and blue eyes (well, if suddenly such an appearance is in fashion), Professor Yong added that she does not exclude this either ...
But we had not an ethical, but, if I may say so, a technical question: are scientists already able to remake our genome and replace blue eyes with brown ones?
What is the human genome (for those who skipped biology classes)
All our life is encoded in DNA molecules - deoxyribonucleic acid. Surprisingly, all these huge molecules consist of a combination of only four basic elements: the nitrogenous bases of adenine, guanine, thymine and cytosine (they are usually denoted for brevity by the first letters - A, G, T, C). The complex sequences of these elements serve as a kind of matrix on which RNA - ribonucleic acids are synthesized. RNA is the "workhorses" of our body, each has its own specialization. Some participate in the synthesis of proteins, setting the correct sequence of elements, others supply amino acids to the site of protein synthesis, and others “reshape” their counterparts by catalyzing reactions involving RNA.
” Personally, our genome reminds me of an anthill: with DNA - an ant queen, endlessly laying eggs, from which RNA ants appear, among which there are soldiers, nannies, workers ...
Wikipedia gives this example: “DNA is often compared to blueprints for making proteins. Expanding on this engineering/production analogy, if DNA is a complete set of blueprints for making proteins stored in a factory manager's safe, then messenger RNA is a temporary working copy of a blueprint for a single part issued to an assembly shop.
Choose your analogy!
DNA molecules are found in every cell in our body that has a nucleus. Molecules - because the famous DNA helix is "chopped" into 46 "pieces" of different sizes, connected in pairs - these are 23 pairs of our chromosomes.
” In each pair of chromosomes, we inherited one from our father, and the other from our mother. The 23rd pair is responsible for our gender, so the chromosomes in it may differ: “XX” for girls, “XY” for boys.
In all autosomes (non-sex chromosomes), both the chromosome inherited from the father and inherited from the mother contain similar genes in the same regions. Similar - because the genes, we all, generally speaking, are different. For example, in the area where the gene responsible for hair color is located, in one chromosome of the pair there will be a blonde mom gene, and on the other - a brunette dad. In this case, one of the genes will dominate, and the second, recessive, will wait in the wings. If it is he who is inherited, and if the same recessive gene is paired with him, then he will have the opportunity to express himself.
” This principle of inheritance of genetic information is fraught with unpleasant surprises. And now we are not at all about the birth of a blue-eyed blond in a family of brown-eyed brunettes, but about hereditary diseases. Sometimes, hidden in recessive genes, they lie dormant for many generations, without showing themselves outwardly. But as soon as such a gene meets its “brother”, tragic consequences are inevitable.
Any parent would like to cut out a malicious gene from their DNA and replace it with a healthy one, protecting their offspring. And here we again return to the question: is it really real?
Genetic engineering and IVF
Svetlana Vladimirovna, genetic analysis during in vitro fertilization, “in vitro conception”, is it already a familiar thing?
” -It has been proven that such “pinching off” of cells does not lead to disruption of the development of the embryo. This method is technically much more complicated and expensive than just a genetic analysis of the fetus during pregnancy, which is performed after taking the amniotic fluid or placental fragment, so it has not yet received wide distribution.
That is, parents can only hope that one day a combination of healthy genes will “fall out” randomly. Is it possible to somehow cut out the "bad" genes?
In most cases, it is not necessary to delete a gene; in fact, pathogenic mutations just “remove” the gene functionally. It is necessary to make a malfunctioning gene work normally. Either cut out the excess from it, or insert the lost one, or replace the wrong one with the right one. A simpler approach is to add a normal copy of the gene to the genome in one fell swoop.
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Mitochondria have their own DNA - organelles responsible for the "energy supply" of the cell. Unlike other chromosomes located in the nucleus, mitochondrial DNA are small circular molecules, their number in a cell varies from tens to thousands of copies and depends on age. The egg is rich in mitochondria, and the sperm cell contains only one, which ensures the movement of its “tail”. After fertilization, this mitochondrion is destroyed, so all human mitochondrial genes are inherited only from the mother. If the cause of the disease is in the mitochondrial DNA, then it is possible to use the mitochondria of the “third parent”. At the same time, the nucleus of the mother's egg cell, which has pathogenic mutations, is transplanted into the cytoplasm of the woman's egg cell with normal mitochondria, and then it is fertilized with the father's spermatozoa and implanted according to the IVF protocol. In particular, the method of cytoplasmic replacement has been successfully used in the case of maternal infertility associated with disorders in mitochondrial DNA. Since 2015, this method of genetic "modification" of a person has been legal in the UK, but is still banned in the US. Australian legislation is preparing for innovations regarding genetic engineering. To get around existing prohibitions, such manipulations are carried out on the territory of countries where there is no relevant legislation, for example, in Mexico and Ukraine.
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By the way, the technology to “remove bad DNA and insert good” has already been put into practice! True, we are not talking about nuclear DNA, which we have talked about so far, but about mitochondrial DNA. Here is what Svetlana Mikhailova says about this.Human DNA modification technologies
- But how can one "operate" a gene, is it really about real technologies?
There are many ways to cut the DNA molecule. People borrowed tools for this from bacteria. Fighting for a place under the sun (or, conversely, in the shade), bacteria synthesize proteins or complexes of proteins and RNA that cut the DNA of other types of bacteria and viruses, but are harmless to the DNA of the hostess and her descendants. These molecules are attached to specific DNA sequences (a specific phrase from the "letters" A, C, T and G), which are obviously not in the host's genome. So “pinching off” is not a problem, the main thing is to sew back the cut molecule correctly. If this is not done, then there will be a break in the chromosome and a violation of the functions of the site where the break is located.
” - Now the most promising tool for a genetic engineer is the bacterial CRISPR/Cas9 system - part of the bacterial immunity, modifications of which are actively used to edit the genomes of eukaryotes (living organisms whose cells contain nuclei - ed.). Bacteria "keep in reserve" in their genome DNA fragments of viruses that they have encountered before. These fragments allow the bacterium to quickly build constructs consisting of RNA and proteins that specifically cut the DNA of viruses. In this case, the Cas9 protein functions as molecular scissors, and the so-called gRNA, which partially contains the genetic sequence of the virus, is a GPS navigation system that directs the “scissors” to a specific region of DNA. Bacteria fight the genes of viruses, but such a biotechnological tool can be aimed at an arbitrary section of the DNA of any organism.
In order for a cell whose DNA was cut in this way to be able to recover, DNA with the desired sequence is injected into it in parallel. The cell starts its own DNA repair mechanisms and uses the added DNA as a template to repair the resulting damage. Thus, it is possible to change one genetic sequence for another!
- Where do they get the "correct" genes?
Almost any human gene can be inserted into the genome of a bacterium, the bacterium can be forced to actively divide, and then the desired fragment can be isolated again in large quantities. Thus, complex animal proteins have not been isolated from animal organs for a long time, but are produced using genes built into bacteria (for example, insulin).
Can genetic engineering give health and brown eyes
- That is, genetic engineering is possible - albeit in the order of a laboratory experiment?
The more complex the body, the more difficult it is to do. To obtain genetically modified laboratory organisms, such approaches have been used for a long time. The scope of these methods is the genetic modification of crops, farm animals, but especially bacteria.
However, it is impossible to directly transfer the approaches developed for experimental organisms to humans. The methods that work on animals and plants are not specific enough. Some of the organisms obtained are not viable, some have “wrong” signs, they are simply discarded. An example is golden rice. It was derived by genetic modification, adding two genes from other organisms to the rice genome, which contributed to the accumulation of beta-carotene in its seeds. Indeed, rice with the desired characteristics was obtained, but its yield was reduced. It is assumed that the reason for this is unfortunate insertion sites for new genes.
With humans, the cost of error is too high, so human experiments are very limited. Any genetic changes - the risk of cell degeneration into cancer or its death. Naturally, it is possible to process a cell culture or, for example, a bacterial colony, but in the end, they try to select only those cells that have certain characteristics that are a sign that the modification of their genome has really occurred.
” - If you treat a multicellular organism, then some of the cells can undergo modification, but some can't. It is impossible to predict which of the cells will subsequently become the precursor of specific tissues of the body, so the effect of such a modification is now unpredictable. Relatively speaking, the cell where the brown-eyed gene is inserted will end up in the heel.
- Is it possible to change the entire genome of an adult?
No, it is now impossible to work with all the cells of an adult, and it is not necessary. An organism that has a severe genetic disorder that affects the function of every cell simply dies prenatally. Genetic disorders compatible with life are mainly manifested in some particular organ or organ system. It is they who will be the targets of genetic engineers. If you want brown eyes, then it is not necessary to modify the DNA of the heels. There are no well-established methods of such manipulations with a stable predictable result on humans, but genetic engineering is developing very quickly, so we are waiting!
- The first experiments on the use of genetic engineering in the treatment genetic diseases has already?
The literature describes the successful experience of gene therapy for epidermolysis bullosa ( a rare chronic hereditary disease, as a result of which wounds are continuously formed on the skin and mucous membranes - approx. ed.). Stem cells from the patient's skin were treated with virus-like particles containing the normal sequence of a gene disabled by mutations. The resulting cells were settled in the damaged areas of the child's skin, and the skin was restored!
There were also attempts to influence the body of an adult. To do this, the necessary genetic material was packed into the shell of an adenoviral particle and the respiratory tracts of patients were treated with an aerosol. Virus particles were attached to epithelial cells and injected into the cells with the DNA of the "desired" gene. Experiments were also carried out on the treatment of virus-like particles with the "correct" genes of the patient's blood cells.
” - In these experiments, the results were also, but unstable. This is due to the fact that the altered cells, although they produced the necessary proteins, did not multiply. Gradually, the “correct” cells died, and the symptoms of the disease returned. Another problem with this method is the body's immune response to these virus-like particles. Many parameters cannot be controlled with this approach; there is a threat of damage to the normal genetic material of cells.
Therefore, now the most promising direction is the modification of a person's own stem cells and launching them back into the body. There are already techniques for taking fibroblasts from the skin, converting them back to a stem cell state, and reprogramming them into some other cell types. This is now actually the cutting edge of science, a lot of effort and finance has been thrown into this (although not in our country). Genetically "corrected" cells grown in this way can help a person overcome AIDS and certain types of cancer.
Transplantation of own mitochondria has recently been used in newborns with cardiovascular pathologies in the United States. Instead of a poorly functioning own heart, with mitochondria destroyed from oxygen starvation, they did not put a donor one; mitochondria obtained from the muscle tissue of children were injected into the damaged area of the heart muscle. The heart cells took over the mitochondria and began to work normally. As a result, eight out of 11 sick children did not need a heart transplant! Although such a manipulation cannot be called genetically engineered, it creates a reserve for the treatment of patients, including "alien" mitochondria.
In general, in medicine, many hopes are placed precisely on the use of their own slightly modified cells, and it is in connection with this, I think, that the legislation in the field of gene modification in relation to humans will be revised.
Interviewed by Irina Ilyina
It may seem that DNA is the main center of the molecule, without which its life is impossible. In fact, DNA is a rather sensitive complex molecule, which itself is capable of rapidly changing and exhibiting special properties. It is influenced by both our thoughts and intentions, as well as physical and chemical influences.
Complex chains of genetic codes, each link of which can stop working or become active at any moment - this is what constitutes the concentration of human genetic material. In addition, gene helixes can exhibit incredible properties and help store energy for an incredibly long time. But how is this possible and how can you tune your body to heal by influencing DNA?
light trap
Photons of light are not delayed, but are constantly scattered. In plants, light energy is converted into nutrient molecules, and in the human body, a helical DNA molecule can serve to capture photons of light. This was proven in an experiment with placing DNA in a quartz container and irradiating it with light. Interestingly, the light itself also acquired a spiral structure and could be stored for a month even after the DNA molecule was removed from the container. Such transformation and storage of light energy is available only to helical molecules, which are responsible for the transmission of genetic information.
Self Healing
Many people believe that heredity plays a major role in health. In fact, experimental data on the importance of positive thinking in managing DNA suggests that genes determine us only in part, while the rest of the person is responsible for his own diseases and tendencies. With stress, irritation, constant experiences, genes stop working normally, prerequisites for the development of diseases arise. Pathologies can affect absolutely any organs and tissues, but it all starts with thinking and self-destructive mechanisms of the impact of consciousness on spiral molecules.
The source of energy for the healing of cellular molecules is love. This is a method of targeted healing rejuvenation of cells, preventing their aging and destruction. Love allows you to increase positive energy and make thoughts stronger. Without love, the body cannot develop normally. This is proved by experimental observations, when children cannot fully develop if they lack parental affection and love. It has been proven, for example, that children from shelters are more likely to suffer from autism than babies who are cared for by their parents.
mental transformations
Structural changes in DNA can be influenced at a distance through intention.
If a person consciously concentrates on good thoughts, and his brain begins to radiate harmonious waves, but the DNA helix begins to transform. Moreover, if a person influences with positive thoughts and intentions, then the changes lead to healing transformations, and if there is directed anger, anger, irritation in the thoughts, then the DNA is tuned to the wave of dying. The thing is that the brain begins to transform thoughts into energy flows that are perceived and interpreted by DNA as signals for the restoration of the body, or, conversely, for self-destruction.
According to the experimental data, there were practically no changes in the structure of DNA placed in an isolated test tube with a neutral medium in the absence of mental influence. But when thoughts were focused on the test tube with DNA, changes began in 10% of the sections of the molecule, which carries genetic information. That's how healers work. They are able to convert positive thoughts and attitudes into brain wave energy. It is these waves that give the cells of the body signals about the need to heal organs and systems.
The work of the nervous system is carried out by means of electromagnetic impulses. Roughly speaking, this means that our entire brain works on magnetism, like a computer processor, and thoughts have a connection with electricity, recording information at the cellular level in much the same way as the head of a cassette tape recorder does. And since a person forms his thoughts into words, then we also encode our reality with language. We'll talk about this later.Of course, the authors of this study did not hear about. All the better. Their information confirms his words without looking for evidence that he is right. DNA is a bioacoustic antenna that not only carries information, but also receives it from outside. Just as thoughts can change the genes in an individual person, the general thoughts of an entire civilization can change its entire reality!
It has been scientifically proven that training the brain and stimulating certain areas of it can have a beneficial effect on health. Scientists have tried to understand exactly how these practices affect our body.
A new study by scientists in Wisconsin, Spain and France provides the first evidence of specific molecular changes in the body that occur after intense mindfulness meditation.
The study examined the results of using clear mind meditation in a group of experienced meditators and compared the effect with a group of untrained subjects who were engaged in a quiet, non-meditative activity. After 8 hours of clear mind meditation, the meditators were found to have genetic and molecular changes, including altered levels of gene regulation and reduced levels of pro-inflammatory genes that are responsible for physical recovery from stress.
“To our knowledge, this work demonstrates for the first time rapid changes in gene expression among subjects practicing clear mind meditation.” says study author Richard J. Davidson, founder of the Healthy Mind Research Center and professor of psychology and psychiatry at the University of Wisconsin-Madison.
"The most interesting thing is that the changes are observed in the genes that are currently being targeted for anti-inflammatory drugs and analgesics" says Perla Kaliman, first author of the paper and researcher at the Institute for Biomedical Research (IIBB-CSIC-IDIBAPS) in Barcelona, where the molecular analysis was carried out.
Clear mind meditation has been found to have a positive effect on inflammatory diseases and is endorsed by the American Heart Association as a preventive intervention. New research results may demonstrate the biological mechanism of its therapeutic effect.
Gene activity can change depending on perception
According to Dr. Bruce Lipton, the activity of the gene can be changed based on daily training. If your perception is reflected in the chemical processes in your body and your nervous system reads and interprets the environment and then controls blood chemistry, you can literally change the fate of your cells by changing your thoughts.
In fact, Dr. Lipton's research clearly shows that by changing your perception, the brain is able to change the activity of genes and create more than thirty thousand variations of products from each gene. The scientist also claims that the gene programs are contained within the nucleus of the cell, and you can rewrite these genetic programs by changing the blood chemistry.
Simply put, this means thatfor cancer treatment we need to first change the way we think.
"The function of our mind is to harmonize our beliefs and real experiences" says Dr. Lipton. “This means that your brain will regulate your body biology and your behavior in accordance with your beliefs. If you were told that you were going to die within six months and your brain believed it, then chances are you will actually die within that time. This is called the "nocebo effect", the result of negative thoughts, the opposite of the placebo effect."
The Nocebo effect indicates a three-part system. Here, the part of you that swears it doesn't want to die (consciousness) plays out the part that believes it will die (doctor's prediction, mediated by the subconscious), then a chemical reaction occurs (reinterpreted by brain chemistry) that is supposed to prove that the body conforms to the dominant belief.
Neurology has recognized that 95 percent of our lives are controlled by the subconscious.
Now let's return to the part that does not want to die, that is, to consciousness. Doesn't it affect body chemistry? Dr. Lipton stated that it all comes down to the fact that the subconscious mind, which contains our deepest beliefs, has been programmed. Ultimately, it is these beliefs that take precedence.
"It's a difficult situation" says Dr. Lipton. “People are programmed to believe that they are victims and that they have no control over the situation. They are programmed from the very beginning by the beliefs of their parents. So, for example, when we are sick, our parents tell us to go to the doctor, because the doctor is the authority that cares about our health. We receive the message from our parents as early as childhood that doctors are responsible for our health and that we are victims of external forces that we cannot control ourselves. It's funny how people get better on the way to the doctor. That's when the innate ability to heal itself kicks in, another example of the placebo effect."
Clear Mind Meditation Affects Regulatory Pathways
The results of Davidson's research demonstrate the down regulation of genes involved in inflammation. Affected genes include the pro-inflammatory genes RIPK2 and COX2, as well as histone deacetylase (HDAC), which epigenetically regulate the activity of other genes. Moreover, a decrease in the expression of these genes was associated with a faster physical recovery of the body after the release of the hormone cortisol in a situation of social stress.
For years, biologists have suspected that something like epigenetic inheritance is going on at the cellular level. Different kinds cells in our body confirm this example. The cells of the skin and the brain are endowed with different forms and functions, although their DNA is identical. So there must be mechanisms other than DNA to prove that skin cells remain skin cells when they divide.
Here's what's amazing: According to scientists, there were no differences in the genes of each of the studied groups before the practices. The above effects were noted only in the clear mind meditation group.
Because several other DNA-modified genes showed no difference between the groups, it is hypothesized that the practice of clear mind meditation affects only a few specific regulatory pathways.
A key finding of the research was that a group of clear-mind meditators experienced genetic changes that were not found in the other group, even though they also engaged in quiet activities. The result of the survey proves the principle: clear mind meditation practices can lead to epigenetic changes in the genome.
Previous studies in rodents and humans have shown a rapid (within hours) epigenetic response to stimuli such as stress, diet, or exercise.
"Our genes are quite dynamic in their expression, and these results suggest that the calmness of our minds may influence their expression." Davidson says.
“The results obtained can be the basis for studying the possibility of using meditative practices in the treatment of chronic inflammatory diseases. » Kaliman says.
Unconscious beliefs are the key
Many practitioners of positive thinking know that good thoughts and constant repetition of affirmations do not always bring the effect that books on this topic promise. This point of view is not disputed by Dr. Lipton, who argues that positive thoughts come from the consciousness, while negative thoughts are usually programmed by a stronger subconscious mind.
“The main problem is that people are aware of their conscious beliefs and behaviors and are not aware of their unconscious messages and behaviors. Many people do not even realize that everything is controlled by the subconscious, a million times more powerful sphere than the consciousness. From 95 to 99 percent of our lives are controlled by subconscious programs.
“Your subconscious beliefs work for you or against you, but the truth is that you are not in control of your life because the subconscious takes the place of conscious control. So when you're trying to heal by repeating positive affirmations, it's possible that an invisible subconscious program is getting in the way."
The power of the subconscious is clearly visible in people suffering from a split personality. For example, when "at the helm" is one of the personalities, a person may suffer from a serious allergy to strawberries. At the same time, it is worth changing the personality - and the same person is able to eat strawberries without any consequences.
We read in the topic:
THEMATIC SECTIONS:
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Certain chemical markers in the human genome change throughout a person's life. This conclusion was made by an international team of researchers after analyzing DNA samples of the same people obtained at intervals of several years. The scientists published their work in the journal Journal of the American Medical Association.
Human DNA molecules carry information about all the features of his body. The information contained in the genome can be roughly divided into two types. The first is the information encoded in the building blocks of DNA - nitrogenous bases. It is inherited and remains unchanged throughout a person's life (if random changes do not appear in the DNA - mutations). Information of the second type is determined by the so-called epigenetic markers - chemical "superstructures" of nitrogenous bases. The inheritance of epigenetic markers does not obey the classical laws of genetics, but they have significant influence on the functioning of the genome.
Until now, scientists have not had a consensus on the changes in epigenetic DNA markers during a person's life. Researchers led by Andrew Feinberg at Johns Hopkins University in Baltimore studied this issue using one type of epigenetic marking, methylation, as an example. The scientists analyzed DNA samples from 111 people from Iceland taken in the early 1990s and 2000s. Volunteers were 69 years of age or older at the time of the second series of samples. To study the methylation pattern, the scientists used a special enzyme that cuts a certain DNA sequence only if it is methylated. By evaluating the number of cuts in the "old" and "new" DNA samples, the researchers determined the difference in the level of methylation.
It turned out that in two-thirds of the volunteers, the level of methylation changed by at least five percent. Approximately one third of the people studied "accumulated" about ten percent of the changes. Interestingly, an increase and decrease in the number of methyl groups in the genome were observed equally often. To understand whether the change in the methylation profile is hereditary, the scientists compared the DNA of 126 people from 21 American families. DNA samples were taken at intervals of 16 years.
The results of these tests were about the same as the results of the previous experiment: in two-fifths of the volunteers, the level of methylation changed by five percent and the frequency of "increases" and "subtractions" of methyl groups was approximately the same. However, in members of one family, either a decrease or an increase in the number of methyl groups in the genome was predominantly observed.
The authors of the work admit that despite the importance of the obtained results, it is not possible to assess their significance today. Epigenetic changes have a significant impact on the functioning of the genome as a whole, but the mechanisms of action of these changes are still very poorly understood.
