What does Down mean?

Down syndrome refers to trisomy 21 syndrome, which we call Down syndrome, also known as Down syndrome. It belongs to a chromosomal lesion. This child often has an extra chromosome. When diagnosed, chromosome examination is needed to make some typing for it, such as whether it is a standard type, mosaic type or ectopic type. 21-trisomy syndrome its main feature is the performance of a child's mental retardation, it also has some special features, special features are mainly manifested as the child's nose bridge is relatively low, eye distance is relatively wide, eye crack is relatively small, ears are relatively small, the outer canthus of both eyes is inclined, often showing a mouth sticking out tongue, special features, its growth and development is slow, can be accompanied by a variety of deformity. Most of them will be accompanied by congenital heart disease, but also can show some gastrointestinal tract abnormalities, cleft lip, cleft palate, multiple fingers, etc., there are such children are often slightly lower immune function, it is easy to get leukemia, boys can also show some cryptorchidism, small penis and so on.