What is Down Syndrome and Who gets Down Syndrome?
Down syndrome is a developmental disorder caused by a chromosomal anomaly in which each cell contains 47 chromosomes instead of the normal 46. It has been determined that an extra partial or complete 21st chromosome results in Down syndrome. Down syndrome is very rarely inherited, it is usually caused by a mistake in cell division during the development of the egg, sperm or embryo. About one in every 700 children born have Down syndrome, as many as 600 are born every year in the United States. Mother at high risk of having children with Down syndrome include those who are trying to have children later in life (the likelihood of a mother having a baby with Down syndrome is as high as one in 30 births after the age of 45) or those who already have a child with Down syndrome.
What are the Signs and Complications of Down Syndrome?
Down syndrome causes mild to moderate mental retardation and those affected often share similar physical characteristics as a result of the extra 21st chromosome, these are:
- Flattened facial features
- Protruding tongue
- Small head
- Upward slanting eyes, uncommon for the person's ethnic background
- Unusually shaped ears
- Poor muscle tone
- Broad, short hands with a single crease on the palm
- Relatively short fingers
- Excessive flexibility
- Slow growth and smaller size compared to those of similar age
Down syndrome can cause many complications, most of which are completely treatable. Some complications of Down syndrome are:
- Heart defects
- Infectious diseases, such as pneumonia, due to a weakened immune system
- Gastrointestinal blockage and problems
- Thyroid problems
- Hearing loss
- Vision problems
How is Down Syndrome Diagnosed?
Screening for Down syndrome is a routine part of prenatal care, especially if the mother has heightened risk factors. The most effective screening test are completed between the 11th and 14th week of pregnancy, ultrasound and certain blood tests—to measure levels of pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotropin—measure certain risk factors that could indicate a baby with Down syndrome. Approximately one in 20 women test positive for one of these factors, but most end up giving birth to healthy babies.
If screening tests show abnormal results amniocentesis, choronic villus sampling—where cells are taken from the placenta to analyze fetal chromosomes, or percutaneous umbilical blood sampling are ordered. If a doctor suspects that a baby has Down syndrome after birth, they will order a chromosomal karotype for the baby to confirm diagnosis.
Treatment for Down Syndrome
There is currently no known medical treatment to cure Down syndrome. Doctors are able to treat other medical complications that may result due to Down syndrome; such as heart defects, leukemia, gastrointestinal problems, and hearing problems. Other medical professionals like physical therapists, speech pathologists and occupational therapists can help develop skills.
The Link Between Celiac Disease and Down Syndrome
Studies have shown that approximately 5-10% of people with Down syndrome also have celiac disease. This is largely because those with Down syndrome are at higher risk of developing autoimmune diseases compared to the normal population.