Genetics is a science that is closely related to the origin and entire history of mankind. In fact, it was she who allowed to reveal the most mysterious part of life and still surprises with her unthinkable discoveries, for example, such as the doctrine of heredity and chromosomal diseases.
If it is very simple to explain the goals and objectives of this science, then we can say that genetics studies and reveals the patterns of inheritance of the human race. For example, it examines both external signs (a special shape of the head, nose, eye color, hair, and much more), as well as internal (features of the enzyme systems). In addition to the fact that man is at the center of the study of genetics, all living organisms on Earth also depend on those processes that were originally laid down at the genetic level.
An excellent field for the study of scientists is the now surviving descendants of the royal dynasties, because the traits inherent in the ancestors are transmitted through a series of generations, and it can be used to judge whether a person belongs to a particular surname or kind.
So, we know that the carriers of hereditary information are genes, each of which is specific and is responsible for a specific process or trait in the body.
A recessive gene plays a special role, because it is he who carries the genetic information of a person, which changes under the influence of another - the dominant gene.
As a rule, hereditary diseases are thoroughly “encrypted” by the recessive gene and do not pose a danger until it encounters the second same “sick” recessive gene.
An interesting fact: a recessive gene may not appear in several generations in a row until this undesirable encounter with the paired gene occurs.
For example, the dynasty of the rulers of the Habsburgs was distinguished by the special structure of the jaw and lips. Artists of those times faithfully displayed these deviations on the family portraits of noble nobles. In the appearance of the representatives of this dynasty, one can clearly see their characteristic features: a thick lower lip, irregular cheekbones, a special shape of the lower eyelids, and an incorrect bite. This is the result of family marriages, where the meeting of recessive genes was realized.
This also applies to internal signs - hereditary diseases, which are inherited from parents to descendants.
The recessive gene, or rather the result of its interaction with similar ones, is considered by scientists as a serious threat to the development and continuation of the human race.
It is believed that the diseases that develop in these cases, very often cause death. The degeneration of the genus, or even the prerequisites for the degeneration of nations, is caused all by the reason hidden under the name "recessive genes." When their percentage increases to a critical state, the population is usually doomed to extinction.
Such a process more often occurs in separate closed societies, or when there is a sharp transition from a large number of offspring to very low birth rates. Recessive genes in such cases occur many times more often. The facts of degeneration have been known to mankind since prehistoric times.
It is currently worrying that defective genes replenish the human population. It can be assumed that with low birth rates they will simply become completely defective.
External and internal characteristics of a person appear as a result of what is inherent in his heredity. Allocate dominant and recessive symptoms. The second can be attributed to the complete absence of pigmentation or albinism, as well as such a deviation as color blindness or color blindness, hemophilia, alopecia in women, deafness, negative Rh factor. An interesting fact is that the inheritance of color blindness goes along the female side, while women themselves rarely suffer from this ailment.
Among the representatives of the weaker sex, these recessive symptoms are common only in 0.5% of cases, and in men, color blindness is more common, in 8% of cases.