Mutation always happens suddenly. The genetic material of an organism changes: something happens inside the chromosomes or genes, and these changes are usually visible to the naked eye. In some cases, the consequences are severe, and sometimes a fatal outcome is possible for the body. Mutation does not occur on its own. The cause is always a mutagenic factor.
What are mutagenic factors?
Changes occurring in genes and chromosomes are studied by the science of genetics. She also gives the scientific definition of mutagens.
Mutagenic factors are chemical or physical agents that cause changes in the genetic material of a cell. The nature of these agents may be different, and their classification is based on this provision.
Types of mutagens
Depending on their origin, physical, chemical and biological mutagens are isolated. Any mutagenic factor can be attributed to one of these three main groups.
The impact of agents hostile to the cell can be directeddirectly on the DNA, and then the molecule of the genetic material loses its original structure. Some mutagens interfere with the process of cell division, and as a result, the hereditary material is distributed incorrectly. However, there are also substances that cannot be classified as mutagens by themselves. But the impact on such a chemical compound of certain enzymes turns it into a real mutagenic factor. These substances that have mutagenic "potential" are called promutagens.
Mutagenic factors. Examples
Mutagens of physical origin include sources of ionizing radiation, exposure to ultraviolet radiation, abnormally high or low temperatures, humidity.
For example, ultraviolet radiation wavelengths above 260 nm are absorbed by a plant leaf cell and cause the formation of uncharacteristic pyrimidine dimers (compounds in the DNA chain) in it, which, in turn, cause errors in reading the genetic material. As a result, new cells receive DNA molecules with a "wrong" structure.
Many chemicals are classified as mutagens and promutagens. Examples are reactive oxygen species, nitrates and nitrites, some metals, medicines, and those substances that did not exist in nature before the advent of mankind (household chemicals, food additives and preservatives).
For example, a pregnant woman may be unaware of her condition and may be taking certain antibiotics that are harmful to the fetus. As a result, the child may developcongenital diseases caused by mutations.
Biological mutagens include viruses, bacteria, waste products of some protozoa and parasites.
The result of exposure of such biological agents to a cell is a process called infectious mutagenesis. For example, the bacterium Helicobacter pylori, which lives in the intestines and stomach of a person, can cause inflammatory processes in the mucosa. Inflammation changes the normal course of redox processes in damaged cells, which also changes the structure of the genetic material in them. The processes of DNA repair and the course of normal division of the molecule are disrupted. The result is mutations.
A few words about the process of mutagenesis
Mutagenesis is the process of mutation itself. By what mechanisms can it occur?
The strongest mutagenic factors cause the so-called chromosomal instability. As a result, the genetic material is either distributed unevenly in the divided cells, or the very structure of the chromosome changes. For example, two chromosomes under the influence of an aggressive agent exchange their parts.
The mutagenic factor can also change the DNA nucleic acid sequence. Interestingly, such mutations are lethal or cause very serious diseases when important nucleotides are affected, but they can occur without pathology if such nucleic acid sequences are not damaged.
How to protect yourself from exposuremutagens?
Mutagenic factors are not ubiquitous, so taking some preventive measures would still be beneficial.
Antioxidants are an important group of compounds that prevent the effects of carcinogens. They can help and protect against all sorts of hostile chemical agents. Examples of antioxidants are vitamins A, B and E, beta-carotenes and flavonoids. These substances are found in very large quantities in vegetables and fruits, as well as in green tea.
It is important to try to protect yourself from exposure to adverse physical agents such as UV radiation or tobacco smoke. For example, Australia has a very large population of fair-skinned people and often has sunny weather. The incidence of melanoma in this country is unfortunately high.
Take antibiotics with care, be mindful of food, and try to minimize your intake of preservatives. Ideally, of course, it would be to adhere to the principles of a he althy diet.
Mutagenic environmental factors are strong. However, it is quite possible to protect yourself from their effects if you are attentive to your he alth.
