Classification of genes - structural and functional

GMOs, perinatal diagnostics, DNA decoding, cloning - a lot of technologies of the present and the future are connected with this science. The classification of genes made it possible to study their functions and the possibilities of change. So, what is known about them today?

Genes

Every cell of any living organism contains all the information about it. In theory, this should be enough to reproduce its exact copy. And all thanks to DNA, which in fact is a genetic passport. Having its samples, you can bring out the long- disappeared species of animals and plants and stop the extinction of those who are under threat.

A gene is an elementary unit of hereditary material. They are added to some larger parts, and they, in turn, make up DNA molecules. In fact, every bit of it is an element of code in the form of a sequence of nucleotides, in which all information about the body is encrypted. And the science that studies what this information is, what the functions of the individual units are, what the structural and functional classification of genes and other related issues are, is relatively young, but has already proved its necessity and shows great potential.

Study

The fact that children inherit some traits of their parents and more distant relatives has long been known. However, for a long time it was absolutely unclear what the mechanism for conveying information about the appearance, nature, illnesses from parents to children, grandchildren and future descendants. At this stage it is worth mentioning the famous Mendel, who formulated the laws of inheritance of certain features, although he did not know how this happens.

A breakthrough in the study of genes has become a matter of time since the appearance of microscopes. The cells were found nuclei, in which mankind was able to look through a few dozen years. The most interesting thing is that the discovery for a long time was in the scientists literally under their noses, but they persistently did not notice it.

The fact is that DNA was first isolated in 1868. But right up to the beginning of the 20th century, many biologists were sure that this substance has the function of accumulating phosphorus in the body, and does not play the role of a repository of full coded information about it. Approximately in the middle of the century some experiments were carried out, which proved that it is the main purpose of DNA. But the method of transmission and the structure of the substance remained unknown.

Decoding the genome

Based on the research of Maurice Wilkins and Rosalind Franklin in 1953, Francis Creek and James Watson suggested that DNA is a double helix. Later, this hypothesis was proved, for which scientists received the Nobel Prize.

Now the science faced the task of deciphering the genetic year, which would allow to answer numerous questions. And here, not only biologists, but also physicists with mathematicians entered the matter. The coding method remained a mystery for ten years, it was clear only that it is a triplet, that is, it includes three nucleotide components. In 1965, finally understood the meaning of all the units, called codons. The cipher was broken.

However, this does not mean that there are no riddles left for scientists. Studies continue to continue, but the classification of genes and their study have given more insight into the nature of some diseases and the ways they are treated. Now people who donate blood can find out what diseases they face, whether the risk is high to inherit these or other health problems from their parents and pass them on to children. This has contributed to serious progress in many areas of medicine.

Functions of the gene

When the appointment of DNA was evident, scientists were interested in the question of what kind of meaning each code unit has, what it answers for, what processes in the body it triggers. And for several decades many researchers have been searching for answers. For all this time it became clear, firstly, that the gene is not an indivisible unit of hereditary information, and secondly, that the conceptual apparatus of scientists is in great need of addition.

A few more terms were introduced, which made it possible to more fully reflect the processes that are observed in practice verbally. But the functions of the gene all remained in a rather vague formulation - the synthesis of proteins and polypeptides. Each DNA site is responsible for its specific substance, and how this affects the body, in most cases it is difficult to say. Researchers have yet to work hard to say that these or other genes, for example, are responsible for eye color, good skin and some features of the heart. Everything is complicated by some properties of DNA.

Classifications

Obviously, each unit of DNA performs some specific tasks, although they are not yet known to mankind. Proceeding from this premise, a modern structural-functional classification of genes has developed. It is used most often, but there are others, more narrowly specialized and taking into account some specific properties of those or other parts of DNA. In general, this classification of genes is understood: structural and regulatory (functional). Each of these varieties, in turn, can be divided into groups. For example, among the regulators there are modifiers, suppressors, inhibitors, etc.

Also, the division of genes by the criterion of influence on viability, implying lethal, semi-lethal and neutral units.

Principal differences

A little higher was considered the generally accepted classification of genes. The structural and functional parts of DNA, according to her, are opposed to each other, but in reality everything is completely different. They can not work separately, and each of these groups is important in its own way.

Structural genes are responsible for the direct synthesis of basic proteins and amino acids. Regulators also affect their work, control their inclusion and deenergization in the process of the development of the organism, and also create other auxiliary substances. By the nature of their impact on the structural part, they are divided into inhibitors, suppressors, intensifiers and modifiers. Their activity allows you to accelerate or slow down the development of certain features.

Properties

Each unit of DNA has a number of characteristics that allow in a relatively small protein molecule to encode all information about the body:

1. Discreteness. Each gene acts as an independent unit.
2. Stability. If no mutations are present, some or other parts of the DNA are transmitted to future generations in an unchanged form.
3. Specificity. Each gene acts on the development of a certain trait.
4. The dosage. A change in the amount of a gene in the body leads to disturbances (for example, Down syndrome - an increase in the number of chromosomes).
5. Pleiotropia. The ability of one gene to promote the development of several features.

Still a lot to learn. Yes, scientists have achieved a lot by reading DNA, understanding has improved even when the classification of genes was formed. Structural and regulatory parts working together, an awareness of the coding mechanism - the last century has become a boom in the development of biology. But there is still a lot to learn.

Prospects for the development of science

Despite the fact that genetics is a relatively young science, it is already obvious that a great future awaits it. The treatment of diseases considered hopeless, the improvement of the properties of plants and animals, allowing the development of agriculture, the restoration of biological diversity - all this is possible now. The main factor hindering further study, experimentation and implementation is ethics. The moral problems that mankind will face, having learned to manage information encoded in DNA, are not yet fully understood.