According to the world Health Organization, one out of 700 babies on the planet is born with down syndrome. It is not associated with any external or internal factors. This ratio does not depend on the climatic zone, country, social level, nationality and health of parents, etc. Boys and girls are born with equal frequency. A child with down syndrome can be born in any family of parents with normal chromosome "set".
Doctors call it down syndrome is a genetic accident. Extra 47th chromosome causes physiological features by reason of which the child is developing slower than his peers (and sometimes even quite different).
Early diagnosis of the presence of "unnecessary" chromosome now spend more during her mother's pregnancy. Physicians estimate the risk of the birth of a baby with down syndrome using ultrasound and biochemical screening. If the probability is high, the mother sent for a deeper examination to the doctor-genetics. To confirm or refute the diagnosis can be the result of a study of the villi of the chorion is the outer embryonic shell and amniocentesis ("verification" of amniotic fluid).
A preliminary diagnosis of "down syndrome" can be put and during the inspection of the already born child, upon detection of characteristic features (light weight, narrow eyes, crooked finger, flat nose, always open mouth, etc.). However, to confirm need chromosome tests.
Despite the fact that down syndrome is not a disease, with it often occur such diseases as myopia, heart disease, hearing problems, and speech. Some related illnesses are treated.
It is wrong to consider children with down syndrome "mentally abnormal"! They can be taught well to speak, read, write, draw, play musical instruments, etc. In this case, the most important is not the treatment in special institutions and "normal" children's activity. Kids with down syndrome are harder to generalize, to prove, to reason and to focus on anything, but they have, for example, a highly developed visual memory, they are easy to remember seen images and learn the lyrics.