Nowadays, biotechnology and genetics are actively developing. In Russia, in the late thirties of the last century genetics and cybernetics suffered a deplorable fate. The “People’s” academician Trofim Denisovich Lysenko, caressed by the Soviet regime, declared genetics a "corrupt girl of imperialism." All developments were discontinued, scientists involved in this science were repressed. After 1956, research was resumed. To obtain accurate experimental results for genetic experiments, genetically pure lines of animals and plants are needed. So what is a clean line in biology?
The basic concept of a clean line
The clean line in genetics is a group of organisms that have some traits that are completely transmitted to offspring due to the genetic homogeneity of all individuals. (From the free encyclopedia).
This is the definition of a clean line in biology.
These organisms are homogeneous because their genetic code is identical. They come from one ancestor, or in plants obtained as a result of self-pollination.
Bringing clean lines, breeders were engaged long before the advent of genetics and the concept of a genetic code. For example, the famous line of Oryol trotters. Initially, all of them were descendants of the famous Smetanka, the trotter of Count Orlov.
Using artificial selection in the offspring were selected signs that were of interest. Now there are 11 clean lines of trotters.
The clean lines of chickens with increased egg production and the clean lines of cows, goats and other farm animals were also bred. What are clean lines and what do they mean for agriculture? This allows you to improve the required properties of animals, increase their livestock, and obtain products of the desired quality.
Natural selection in clean lines
Gregor Mendel, the founder of modern genetics, was also interested in what pure lines are, and he was engaged in their breeding in plants. Mendel used 22 similar lines of peas. Exploring the variability in organisms, he formulated his famous laws. In addition, he noted that clean lines in natural selection are often not viable.
In the wild, when changing external conditions, a population with a certain set of genes often cannot quickly change.
Laboratory mice
It is difficult to overestimate the importance of laboratory mice for science. They are used both in clinical trials and as experimental animals. The mice are interested in researchers, because they reproduce very quickly. Laboratory mice were bred in the 19th century by closely related crosses (inbreeding). After 18-20 generations, animals are genetically absolutely identical.
They are used in research and in medicine. Since they are absolutely identical, it is possible to compare the group receiving a particular drug and the control. Moreover, the results are objective and repeated, which is impossible to achieve using ordinary animals.
True, some scientists believe that calling laboratory mice a clean line is wrong.
Individuals of one group may externally differ from each other. This describes the concept of "reaction rate," that is, the possible range of differences in external characteristics.
So, what is a clean line, it is also well understood by the example of self-pollination of plants.
The use of pure plant and animal lines in breeding together with modern methods of genetic engineering promise fantastic results. Maybe there will be no need to kill animals for meat? As in science fiction, will animals give meat from a living body? (And painless?) Or will we have plants that are not afraid of pests and with increased productivity?