Why are babies born down?
From the birth of a child with Down syndrome, no family is insured. You can lead an exceptionally healthy lifestyle, play sports, have no bad habits, have a full medical examination once a year - all this does not give you any guarantee that you will not have such a baby. For a long time, people did not understand why such strange children appear from time to time, not like their healthy relatives. Everything became clear when scientists came close to studying the human genome and determined the karyotype, that is, the human chromosome set. It was then that genetics were able to finally answer the question of why children are born downs.
It was reliably established that the karyotype of a healthy person is represented by twenty-three pairs of chromosomes. Trisomy of the twenty-first pair and causes Down syndrome in a child. Now we will try to explain to you from what children are born downs in a simpler language.As we have already said, a normal person has forty-six chromosomes in the nucleus of each cell, and a child with Down syndrome has one more number — 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 syndrome.
An extra chromosome resulting from an abnormal division of germ cells is a spontaneous genomic mutation, a genetic coincidence, a kind of bad joke of the Lord God. This pathology is not inherited, occurs with the same frequency in boys and girls, and is observed in representatives of all races. Down syndrome is not treated, because it is not a disease, but a congenital non-hereditary disorder in the development of the organism. Therefore, in a family where there is a child Down, all other children can be completely healthy.
Age of the woman in labor
Because of what exactly the cells suddenly begin to divide incorrectly, it is still not known for certain. However, genetics, while searching for an answer to the question of why children with Down syndrome are born, have deduced one particular pattern. They noticed that the risk of having a baby Down increases significantly with increasing age of the woman in labor.So if the chance to give 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 he is already growing to five percent, so giving birth at that age is very risky.