Why do you have Down syndrome

summary

I believe those who have studied biology should know down's syndrome, which is often called trisomy 21. It is a congenital disease caused by chromosomal abnormalities. Let's talk about why it is.

Why do you have Down syndrome

First: Down's syndrome, also known as Down's syndrome, is a disease caused by chromosomal abnormalities (one more chromosome 21). 60% of the patients had abortion in the early intrauterine period. The survivors had obvious mental retardation, special face, growth and development disorder and multiple malformations.

Second: the child has obvious special facial signs, such as wide eye distance, low and flat nasal root, small eye fissure, oblique lateral eye, epicanthus, small outer ear, fat tongue, often extending out of the mouth, salivation. Short stature, less than normal head circumference, short anterior and posterior head diameter, flat occipital head. The neck is short and the skin is loose. Bone age often lags behind age, and tooth emergence is delayed and often dislocated. The hair is soft and thin.

Third: cytogenetic studies found that when the 21q22 band of chromosome 21 is trisomy, the individual has clinical manifestations completely similar to Down's syndrome, on the contrary, the individuals with non trisomy have no such typical symptoms. Therefore, 21q22 region may be the key region of Down's syndrome gene, also known as Down's syndrome region.

matters needing attention

According to the relevant medical data, the incidence of Down's syndrome is related to the pregnant age of the mother. The elderly pregnant women are much more likely to suffer from this disease than other people. Therefore, the elderly pregnant women must do the prenatal examination on time, so as to eliminate this risk.