Scientists have discovered why children of addicts inherit their addiction to drugs

© Fotolia / psdesign1Модель DNA moleculesScientists have discovered why children of addicts inherit their addiction to drugs© Fotolia / psdesign1

. The unusual experiments with rats have shown that the propensity to use drugs can be passed from father to son because drugs change the structure of the protein «packaging» the DNA of parents, said in an article published in the journal Nature Communications.

The genetic material of humans and all other living beings separate from the cell nucleus is Packed in special proteins-histones, which hold the folded DNA in place and do affect «readability» of individual genes.

In recent years, geneticists are finding more hints that this is a «wrapper» DNA is involved in the transmission of information between generations, and allows animals and plants to adapt quickly to new environmental conditions, and problems with the «overwrite» special marks on its surface were associated with a predisposition to homosexuality and suicide among people.

Le Cumini (Le Qiumin) from Fudan University in Shanghai (China) and his colleagues have discovered another unusual link between epigenetics and behavior of people and animals, watching the varied behavior of the young rats that took cocaine for a long time before procreation.

As the scientists, drugs in the «family» of rodents was taken only by the father – mother never touched cocaine, which excluded the possibility of developing dependence have her cubs during fetal development due to the penetration of drug molecules into the fruit.

Grow their offspring, scientists have connected them to the same cocaine «drip» as their fathers, and allowed them to press the button that injected a portion of the drug in their body. Watching their behavior and actions of the offspring of rodents in the control group, the scientists tried to understand, did the drug use of their father on their propensity to use cocaine.

It turned out that this is indeed the case in these rats addicted to cocaine has grown faster and their brains were much more responsive to the drug than other cubs. For example, a week after the start of the experiment they are about 1.5 times more often clicked on and behaved much more actively in the presence of the drug than their relatives.

Interestingly, this reaction was typical for the next generation of pups, even if their parents never used cocaine. All of this suggests that rats have inherited the increased vulnerability to the action of drugs, and that these changes can be passed from a father to his children.

After analyzing the differences in their brains and other parts of the body, scientists came to the conclusion that such inheritance of predisposition to drug use was associated with changes in the structure of the protein «packaging» of their DNA that occurred in the body of their father.

This is supported by the fact that Coming and his colleagues have documented thousands of changes in the structure of these proteins in the development of dependence in even first-generation rodents. About half of these changes persist in the DNA of their children and grandchildren.

If something similar is true for humans, it is, as scientists believe, a good explanation of why alcohol and drug abuse often develop a «family» and hereditary. It is possible that restoration of the normal structure of epigenetic marks during fetal development can help children of former alcoholics and drug addicts to avoid repeating the fate of their fathers and mothers, the scientists conclude.