Why are children born?

From the birth of a child with Down's syndromeno family is insured. You can lead an exceptionally healthy lifestyle, play sports, not have any bad habits, once a year undergo a full medical examination - all this does not give you any guarantees that you will not have a baby like that. For a long time people did not understand, from which from time to time there are such strange children, unlike their healthy relatives. Everything cleared up when scientists came close to studying the human genome and determined a karyotype, that is, a chromosome set of a person. Then the geneticists could finally answer the question of why the children of the down are born.

Excess chromosome

It was reliably established that the karyotypea healthy person is represented by twenty-three pairs of chromosomes. Trisomy for the twenty-first pair and causes Down's syndrome in a child. Now we will try to explain to you, from what the children of Down are born in a simpler language. As we have already said, a normal person in the nucleus of each cell contains forty six chromosomes, and a child with Down's syndrome has one more - forty-seven. The presence of an extra, third chromosome in the twenty-first pair and leads to the fact that the child is born with Down's syndrome.

Extra chromosome, which appeared as a resultwrong division of the sex cells is a spontaneous genomic mutation, a genetic accident, a kind of bad joke of the Lord God. This pathology is not inherited, with the same frequency found in boys and girls, and is observed in representatives of all races. Down's syndrome is not treated, because it's not a disease, but a congenital non-hereditary disorder in the development of the body. Therefore, in a family where there is a child Down, all other children can be absolutely healthy.

Age of the woman in childbirth

Because of what exactly the cells suddenly startit is not known to share correctly until now. However, genetics, while searching for an answer to the question of why babies with Down syndrome are born, have derived one definite pattern. They noticed that the risk of giving birth to a Down's child increases significantly with the age of the woman giving birth. So if the chance of giving birth to a sick child in a twenty-year-old woman is very small, less than one-tenth of a percent, then by the age of forty, it increases to five percent, so it's very risky to give birth at that age.