Down syndrome is a genetic disorder caused by the presence of an extra third strand in chromosome 21, which is why it is also known as Trisomy 21. Thus, a person suffering from Down syndrome has 47 chromosomes instead of the normal 46 – 23 pairs with a single additional chromosome 21. Down syndrome impedes normal development of the body and the mind. People suffering from this disorder are usually short in stature and tend to be overweight. Their eyes are not properly aligned and they commonly suffer from hearing problems as well. Mental retardation is also a common characteristic feature of this condition. Down syndrome also compromises the body’s natural immune system, with the result that the patient falls prey to several infections and diseases. Not only is the growth of muscles, nerves and bones hampered due to this ailment but the general vulnerability of the system makes such people easy prey to serious complications like cancer and Alzheimer’s disease. Many of the patients are born with heart ailments. All of these factors adversely affect the quality of life of the patient and this could lead to premature ageing and death.
The exact cause behind the appearance of an extra chromosome has not yet been ascertained. However, it has been observed that if either or both the parents are well past their youth at the time of the conception of the baby, the risk of him/her being born with Down syndrome increases significantly. Couples past the age of 40 are particularly at risk of bearing babies with this genetic defect. Also, the baby may suffer from this disorder in spite of the fact that both the parents are perfectly normal. It is also believed that if the would-be mother smokes and drinks excessively during pregnancy, she exposes the growing fetus to an increased risk of suffering from this condition.
Though medical research on this condition is going on, as of now Down syndrome is an incurable disorder. It is advisable, therefore, that all pregnant women, especially those above the age of 35, should get a blood test and an ultrasound scanning done in the first trimester of the pregnancy. This helps determine if there is any genetic anomaly in the developing fetus. If the tests reveal that the unborn baby is suffering from a genetic ailment, the decision to terminate the pregnancy or to carry on with it should be left to the parent(s).