The information that codes for all the proteins in the body is written in the cell's DNA. Only 4 types of nucleic bases - and countless combinations of amino acids. Nature made sure that each failure was not critical and made the genetic code redundant. But sometimes the distortion still creeps in. It's called mutation. This is a violation in the recording of the DNA code.
Useful - rare
Most of these distortions (more than 99%) are negative for the organism, which makes the theory of evolution untenable. The remaining one percent is not able to provide an advantage, since not every mutated organism gives offspring. Indeed, in nature, not everyone has the right to reproduce. Cell mutation occurs more often in males - and males, as you know, die more often in nature without giving offspring.
The women are to blame
However, man is an exception. In our species, the process of mutation is most often triggered by the irresponsible behavior of females. Smoking, alcohol, drugs, STDs - and a limited supply of negatively affected eggs.exposure from early childhood. If for men there is a safe dose of alcohol, then for women even a small glass can provoke violations of the proper formation of eggs. While European women enjoy freedom, Arab women abstain - and give birth to he althy children.
Misspelled
A mutation is a permanent change in DNA. It can affect a small area or a whole block in the chromosome. But even a minimal disruption shifts the DNA code, forcing the synthesis of completely different amino acids - therefore, the entire protein encoded by this site will be inactive.
Three types
A mutation is a violation of one of the types - either inherited, or a de novo mutation, or a local mutation. In the first case, these are hereditary diseases. In the second - a violation at the level of the sperm or egg, as well as the consequences of exposure to hazardous factors after fertilization. Hazardous factors are not only bad habits, but also unfavorable environmental conditions (including radiation). A de novo mutation is a disturbance in all the cells of the body, as it arises from an abnormal source. In the third case, a local, or somatic, mutation does not occur at an early stage and does not affect all cells of the body, with a high degree of probability it is not transmitted to offspring, unlike the first and second types of disorders.
If problems arise in the early stages of pregnancy, then a mosaic disorder occurs. In this case, some of the cells areaffected by the disease, some are not. With this species, there is a high probability that the child will be born alive. Most of the genetic disorders cannot be seen, because in this case miscarriages often occur. The mother often does not even notice the pregnancy, it looks like a delayed period. If the mutation is harmless and occurs frequently, it is called a polymorphism. This is how blood types and colors of the iris originated. However, polymorphisms may increase the likelihood of some diseases.
