What is Down Syndrome?
Down Syndrome Symptoms
Down syndrome is a genetic condition that affects a person’s development. Roughly 1 in every 700 infants born in the United States is born with Down syndrome, making it the most common chromosomal condition in existence.
People with this syndrome normally exhibit physical features related to Down’s, including:
- A flattened face that is especially large near the bridge of the nose
- Eyes with an almond shape that slant upward
- A shortened neck
- Low muscle tone
- Short Stature
- Presence of a palmar crease, which is a deep line across the palm of the hand
- Small ears, hands, and feet
What Causes Down Syndrome?
Every cell in the human body has 23 pairs of chromosomes, which are inherited from the individual’s parents. Down syndrome is caused by an extra partial or full copy of chromosome 21.
The reason behind the appearance of this additional chromosome is unknown. The only influential factor that has been identified is the mother’s age at the time of conception, as women over the age of 35 tend to have a higher risk of birthing a baby with Down’s.
Types of Down Syndrome
Few people realize that there is more than one type of Down syndrome. Though they are all similar, there are notable differences between each variation that sets each kind of Down syndrome apart from one another.
The most common form of Down syndrome is called Trisomy 21. In this case, every single cell within the body has 3 distinct copies of the 21 chromosome rather than the typical 2 copies that you would find in another person’s cells.
Translocation Down Syndrome
About 3% of all people with Down’s will have a form of the syndrome known as Translocation Down syndrome. Persons with this type of Down’s still have the extra chromosome 21, but instead of being attached to chromosome 21, it is placed elsewhere among the other chromosomes.
The final kind of Down syndrome is Mosaic Down syndrome. Only about 2% of all people with Down’s will have this specific type of the syndrome, which presents itself as a sort of mixture within the chromosomes. For example, an individual may have 3 copies of chromosome 21 in some cells, but not in others. This often causes people with this type of Down’s to display diluted physical effects of Down syndrome.
Diagnosis of Down Syndrome
There are several ways to diagnose Down syndrome before the child has been born. These methods include screening tests, blood work, and other diagnostic tests to examine the baby’s chromosomes and determine the probability of them being born with Down syndrome.
Diagnostic tests are unlikely to be performed unless there is enough evidence to support them from the initial screening.
Health Concerns Associated with Down Syndrome
It is generally unlikely that a child born with Down syndrome will develop another serious birth defect, but it is possible. Some of the most common health conditions related to Down’s are:
- Eye Diseases
- Hearing Loss
- Heart Defects
- Sleep Apnea
- Frequent Ear Infections