Genetic information: recessive and dominant genes

What is a gene?

A gene is a specific sequence of nucleotides of deoxyribonucleic acid, in which genetic information is encoded (information concerning the primary structure of protein molecules). The DNA molecule is double-stranded. Each of the chains carries a certain sequence of nucleotides. The primary structure of the protein, which is the number and sequence of amino acids, plays a decisive role in hereditary traits. In order for the encoded information to be correctly and regularly read, the gene must have an initiation codon, a termination codon and semantic codons that directly encode the desired amino acid sequence. The codons are three consecutive nucleotides that encode a specific amino acid. The codons of UAA, UAG, CAA are empty and do not encode any of the existing amino acids, when they are read, the replication process stops. Remaining codons (in the amount of 61 pieces) encode amino acids.

Define dominant and recessive genes. A dominant gene is a sequence of nucleotides in which the manifestation of a particular feature is provided (regardless of which type of gene is in the same pair (referring to the recessive or dominant gene)). A recessive gene is a sequence of nucleotides in which the manifestation of a trait in a phenotype is possible only if the same recessive gene is present in the pair.

Such information carries only genetic data that can be transmitted from generation to generation. However, only the variants of the combination of genes determine the manifestation of a particular trait. If the pair contains a recessive and dominant gene, then the property encoded by the dominant gene will phenotypically manifest itself. And only in the case of a combination of two recessive genes is their information manifested. That is, the dominant gene suppresses recessive.

Where do genes come from?

The information that genes bring to us comes from our ancestors. These include not only parents, but also grandparents and other blood relatives. An individual set of genes is formed by the fusion of the spermatozoon and the oocyte, or more precisely, by the fusion of X and Y chromosomes or two X chromosomes. From the father can bring the information of both X and Y chromosome, whereas from the mother - only the X chromosome.

It is known that the X chromosome contains more information, so women are more resistant to diseases of a different nature than the male population. In theory, the number of newborn boys and girls should be equal, but in practice, boys are born. As a result, proceeding from these two facts, there is a balancing of the two sexes. The higher fertility of the male population is compensated by greater resistance to all kinds of impacts characteristic of women.

Genetic Engineering

At the moment, there is an intensive study of genetic material. Methods for the isolation, cloning and hybridization of individual genes have been developed. This is the most important step in the creation of the future. Such close attention to this issue has provoked many hypotheses and hopes. After all, a detailed study can allow mankind to plan the properties and signs of the future generation, to avoid many diseases and to grow organs and their systems for transplantation.