What is the human genome? How long has this term been used in science and medicine, and why is it so important today?
The human genome is the totality of hereditary material contained within a human cell. It consists of 23 pairs of chromosomes.
Genes are individual pieces of DNA. Each is responsible for a trait or part of the body: height, eye color, etc.
When scientists manage to fully “decode” the information recorded in DNA, people will be able to fight those diseases that are inherited. Moreover, it may then be possible to solve the problem of aging.
Previously, it was believed that the number of genes in our body was over a hundred thousand. However, recent international research has confirmed that there are approximately 28,000 genes in our bodies. To date, only a few thousand of them have been studied.
Genes are unevenly distributed throughout the chromosomes. Why this is so – scientists do not yet know.
The cells of the body are always reading the information that is recorded in the DNA. Each of them does its own job: carrying oxygen around the body, destroying viruses and bacteria, etc.
But there are also special cells – sex cells. In men they are sperm cells and in women they are oocytes. They do not contain 46 chromosomes, but exactly half of them – 23.
When the sex cells fuse, the new organism has a full set of chromosomes: half from the father and half from the mother.
This is why children are somewhat similar to each of their parents.
Several genes are usually responsible for the same trait. For example, our height depends on 16 pieces of DNA. At the same time, some genes affect several traits at the same time (for example, those who have red hair have a lighter skin tone and freckles).
A person’s eye color is determined by two genes, and the one responsible for brown eyes is dominant. This means that it has a greater chance of showing up when it “meets” the other gene.
Therefore, a brown-eyed father and a blue-eyed mother are likely to have a brown-eyed baby. Dark hair, bushy eyebrows, dimples on the cheeks and chin are also dominant traits.
But the gene responsible for blue eyes is recessive. Such genes are much rarer if both parents have them.
We hope that now you know what the human genome is. Of course, in the near future, science may surprise us with new discoveries in this area. But this is a matter for the future.