Down Syndrome : Causes, Types and Characteristics
What is Down syndrome?
It is a set of physical and mental traits which is caused by a genetic disorder that takes place before birth.
Children who have Down syndrome usually tend to have certain features.
They may face impairments in terms of cognitive ability and their physical growth is also likely to be affected.
The degree of disability varies from person to person and it can range from mild to moderate.
Down syndrome is unfortunately a lifelong condition.
However, with adequate care and support the children who have this syndrome can grow up to have healthy and prosperous lives.
Causes: Normally, each and every cell in the human body contains exactly 23 pairs of chromosomes which means that there is a total of 46 chromosomes in each cell.
Half of each chromosome pair comes from the mother and the other half comes from the father. Most people who suffer from Down syndrome have an extra 21st chromosome which means they have a total of 47 chromosomes.
The reasons behind this phenomenon are not really known.
The only thing which is apparently related is the mother’s age.
It is clearly noticeable that the children who are born to older women have a higher chance of having this disorder.
Types of Down Syndrome: There are three different types of down syndrome: trisomy21, mosaicism and translocation.
Trisomy21 or nondisjunction is the one which is seen most commonly and it accounts for about 95% of the total cases of Down syndrome.
In this condition, the extra 21st chromosome is replicated in every cell of the body.
In the case of mosaicism there is a mixture of cells, some of which contain the usual 46 chromosomes and some others which have the additional 47th one.
In translocation, though the number of chromosomes remains 46, an additional copy of chromosome 21 gets attached to some other chromosome.
The unique characteristics which the children with Down syndrome exhibit include distinctive facial features such as slanting eyes, a flat face, smaller ears, a short neck and comparatively shorter arms and legs.
The joints are loose and the muscle tone tends to be lower.
They are usually mentally retarded and as a result their intelligence levels can be below average.
Despite the seriousness of this particular health condition, there are measures which can be taken in order to counter it.
Having adequate knowledge about the potential hazards and abiding by the guidelines can prove to be beneficial.