Down syndrome is an abnormality of the chromosomes. It is caused due to erroneous disjunction of chromosomes during cell division. The disorder is named after the doctor who described it, in 1866, Dr John Langdon Down. Each of the cells present in our body contains chromosomes, which occur in pairs - one from each parent. Each cell contains 23 pairs of chromosomes. When chromosomes fail to separate fully at the time of cell division, it results in an extra chromosome in the sperm or egg and that leads to Down’s syndrome. It manifests itself in the form of impairment of the cognitive ability, physical growth and facial appearance of the baby. The exact causes behind the presence of an extra chromosome are not yet known, but a link with older mothers has been found. The abnormality occurs in all races, social classes and countries across the world. Read on to get more information on Down’s syndrome.
Types Of Down Syndrome
- Trisomy 21 - This type of Down's syndrome involves the presence of extra genetic material in the 21st pair of chromosomes. Around 95% of the people suffering from Down syndrome have Trisomy 21.
- Translocation - In this case, the extra genetic material of the 21st pair of the chromosomes breaks and becomes attached to another one. Around 4% of the Down syndrome patients suffer from Translocation.
- Mosaicism - In this type of Down's syndrome, only some of the cells have Trisomy 21. Only 1% of the patients suffering from Down's syndrome tend to have this problem.
Features Of Down Syndrome Babies
After exploring what is Down's syndrome and what are the main types of the abnormality, we will now have a look at the characteristic features of Down syndrome babies. Children born with the abnormality have certain distinguishing physical characteristics, though they may vary from one child to another. The general physical appearance of the children manifests in the form of:
- Smaller than normal head, or microcephaly
- Broad forehead, flattened nose and protruding tongue
- Upward slanting eyes, which may have a filmy fold in the inner corner
- Short, broad hands with short fingers
- Palms that may have just one crease, rather than many, called a simian crease
- Varying degrees of intellectual retardation
- Lower than average birth weight
- Weight gain being at a slower pace than other babies
- Head being flatter than other babies
It is seen that children suffering from Down's syndrome tend to grow up and live a successful and fulfilling life. However, they do need the right support and environment for growth, mainly from their family members. Special provisions for them can make their growth and development process a lot easier. There are quite a number of examples, like actors Stephane Ginnsz, Isabela Pujols, Paula Sage, Chris Burke and other, who despite suffering from Down syndrome, became notable individuals, due to their own talent and the right support system.