Genetics

To understand that it is genetics we must go back to the shocking Mendel's theories when he sought why we possess physical traits similar to our ancestors, traits which Darwin tried to explain through the theory of the evolution of species. A curious fact data that Mendel at the time of Exit Darwin's theory had already managed to solve the great dilemma of genetics, although this discovery only came to light when Mendel died in January 84, in the Great Czech Republic.

Mendel established three essential laws. which are:

1. Principle of uniformity of the hybrids of the first generation subsidiary:

It establishes that if two pure races are crossed (a dominant homozygous with a recessive one) for a certain character, the descendants of the first generation will be all equal with each other, phenotypic and genotypically, and the same phenotypically to one of the Progenitors (of dominant genotype), regardless of the direction of crossbreeding. expressed with capital letters the dominant ones (A = yellow) and lowercase the recessive ones (a = green), would be represented thus: aa x AA = AA, AA, AA, AA. In short, there are factors for each character which separate when the gametes are formed and re-unite when fertilization occurs.

2. Segregation principles:

This law establishes that during the formation of the gametes, each allele of a pair is separated from the other member to determine the genetic constitution of the subsidiary Gamete. It is very common to represent the possibilities of hybridization by means of a Punnett box.

Mendel obtained this law by crossing different varieties of heterozygote individuals (diploids with two allelic variants of the same gene: AA) and was able to observe in his experiments that he obtained many peas with yellow skin characteristics and others (less) with Green skin characteristics, found that the proportion was 3/4 yellow and 1/4 Green (3:1). AA x AA = AA, AA, AA, AA.

3. Principle of independent distribution of alleles

It is sometimes described as the 2nd law, if one considers only two laws (criterion based on which Mendel only studied the transmission of hereditary factors and not its dominance/expressiveness). Mendel concluded that different traits are inherited independently from each other, there is no relationship between them, so the inheritance pattern of a trait will not affect another's inheritance pattern. It is only fulfilled in those genes that are not linked (ie, that are in different chromosomes) or that are in very separate regions of the same chromosome. In this case the offspring follows the proportions. Representing with letters, of parents with two characteristics AALL and AALL (where each letter represents a characteristic and the dominance by the upper case or lowercase), by intersecting of pure races (1st law), applied to two traits, would be the following Gametes: Al x al = Al, Al, Al, al.

"Therefore, there is no doubt that all the characters that intervened in the experiments apply the principle that the descent of the hybrids in which several different essential characters are combined, presents the terms of a series of combinations, which It results from the meeting of the development series of each pair of differential characters. "

Gregor Mendel

To conclude, we can say that, since its beginnings with Mendel, Genetics has sought to answer enigmas about the formation of being, both internal and external. And that, with the contributions of a man like Mendel, one could get to enhance this science, since the study of genetics has contributed with treatments for diseases, deformities of the body; Solve criminal riddles. However, cloning is a field to be cared for, so there are those who claim that all of this becomes negative when they lose sight of the "bioethical" limits. Because you cannot play with life, because creating it in a laboratory is not the same as generating it.