What is a gene?
A gene is a specific nucleotide sequence of deoxyribonucleic acid in which genetic information is encoded (information regarding the primary structure of protein molecules). The DNA molecule is double-stranded. Each of the chains carries a specific nucleotide sequence. 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 necessary amino acid sequence. 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. The remaining codons (in the amount of 61 pieces) encode amino acids.
Dominant and recessive genes are isolated. A dominant gene is a sequence of nucleotides in which the manifestation of a particular trait is provided (regardless of which type of gene is in the same pair (meaning a recessive or dominant gene)). A recessive gene is a nucleotide sequence in which the manifestation of a trait in a phenotype is possible only if the same recessive gene is present in a pair.
Such information carries only genetic data that can be transmitted from generation to generation. However, the manifestation of one or another trait depends only on variants of the combination of genes. If a pair contains a recessive and dominant gene, then the property encoded by the dominant phenotypically appears. And only in the case of a combination of two recessive genes is their information manifested. That is, the dominant gene suppresses the recessive.
Where do genes come from?
The information that genes carry 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 during the fusion of the sperm and egg, or rather, when the X and Y chromosomes or two X chromosomes merge. Information from the father can bring both the X and the U chromosome, while from the mother only the X chromosome.
It is known that the X chromosome contains more information, therefore women are more resistant to diseases of various 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, based on these two facts, there is a balancing of the two sexes. The higher fertility of the male population is offset by greater resistance to various influences characteristic of women.
Genetic Engineering
An intensive study of genetic material is currently underway. Methods for the isolation, cloning, and hybridization of individual genes have been developed. This is a crucial step in creating the future. Such close attention to this issue provoked many hypotheses and hopes. After all, a detailed study can allow humanity to plan the properties and signs of a future generation, avoid many diseases and grow organs and their systems for transplantation.