Down syndrome is probably almost as old as history itself. They appear in 7th and 8th century writings, and many works of art. Before modern terms, the life expectancy of a child born with Down Syndrome was relatively short, due to inferior medical knowledge of the day. Most of these children were taken and reared in convents where they became affectionately known as “Children of God”.
It was in 1866 that Dr Langdon Down, an English physician, first described the Syndrome and remarked on the resemblance of the facial features to those of the Mongolian race, hence the unfortunate use of the words “Mongolian” or “Mongoloid”. There are other features noticeable at birth, but the most common of which is poor muscle tone. Certain abnormalities in the heart or intestines may also be present and can be detected by doctors in the early days of life. The feature which most concerns parents at this early stage is intellectual disability.
What Causes Down Syndrome?
Down syndrome is an accident of nature. No one is to blame. The mother’s food, medication, physical activity or emotional condition will not result in the birth of a child with Down syndrome. It happens because there is an imbalance of chromosomes in either the development of the egg or sperm, or in the first or second division of the fertilized egg when an extra chromosome appears. So there is an error in the correct number of chromosomes to be found in the cells of the new growing baby.
Each cell of the human body contains 23 pairs of chromosomes (for a total of 46 chromosomes), and each chromosome controls up to some thousand genes which govern growth and development. A child with Down syndrome has 47 chromosomes instead of the usual 46. The smallest chromosome (21) is present in triplicate rather than as a pair. Although the genes of these number 21 chromosomes are normal, because there are three instead of two, the genes balance is upset and thrown out of harmony, and so alterations in development are produced. Therefore, it is not surprising that as the body grows, there are alterations in every cell and tissue of the body, including the brain cells. These characteristics we know as Down syndrome.