Down syndrome demystified

by Sophia Grant

UP SYNDROME - PART 1 OF 2 documentary Down Syndrome Down's

In 1866, Dr. John Landon Down first published his work on a group of people with mental retardation under his care in Surrey, England. He described the physical features as resembling people from the Mongoloid race. Use of "mongoloid" to describe those with the syndrome has fallen out of favor, and now Down Syndrome (also seen as Down's Syndrome, either is correct) is routinely used.

Down Syndrome (Trisomy 21) is the most common human chromosomal abnormality. Humans have 46 chromosomes, however those individuals with Down Syndrome have 47 chromosomes. Instead of two number 21 chromosomes, they have three. One might think, "more would be better." However, this additional chromosome adversely affects the delicate balance known as the human genome.

The extra chromosome is located in every single cell of the body and causes a host of physical and mental problems. Most of us recognize the physical appearance of Down Syndrome: flat facial features, up-slanted eyes, short stature, and protruding tongue. However, there are numerous other physical abnormalities of Trisomy 21. Some of them include heart disease, hearing loss, crossed-eyes (strabismus), thyroid disease, leukemia, obesity and seizures. The mental problems of Down Syndrome include retardation and a significant likelihood of developing Alzheimer Disease after the age of 40.

Some individuals are known as mosaics; half of their cells are normal and the other half has 47 chromosomes. Although they have Down Syndrome, these mosaics have a milder case. For instance, intelligence may be higher and the typical features may not be as prominent.

Down Syndrome is now frequently diagnosed in pregnancy with a combination of tests. A "triple screen" tests for a specific protein in the mother's blood. This test, however, frequently comes back elevated when the feetus is, in fact, normal. Cells collected from an amniocentesis and chorionic villi sampling is the only way to know with certainty whether your child has any chromosomal abnormality. These tests are more invasive than the blood tests and do carry more risks.

Trisomy 21 has a higher incidence of occurrence in babies born to women over 35, with an incidence of 1 in 270, compared to an incidence of I in 1500 in those ages 15-39 and I in 800 in those ages 30-34.

If a child has Down Syndrome, there are certain things that have to be done to ensure the health and best possible outcome for a baby:

Evaluation by a cardiologist to rule out congenital heart disease
A hearing test to check for hearing loss
Enrollment in an early intervention program to help with coordination and issues related to muscle tone
Screening for neck instability, especially prior to sports participation
Early screening for cataracts and glaucoma

The outcome for those with Down Syndrome depends on the presence of other associated findings. Barring other complications, people with Down Syndrome can live well into their 60s.

Like most situations that occur in life, the outcome of your experience with a Down Syndrome child will depend on your approach. If you perceive your child as a burden, this indeed will come to pass. If you accept the joys and frustrations that come with raising a Special Needs child, you will be blessed.

For further information contact the National Down Syndrome Congress at www.ndsccenter.org/.

Sophia Grant, M.D., F.A.A.P. is a practicing pediatrician in Southern California. She owns and operates the website www.MomtoMomPediatrics.com, emphasizing practical parenting and pediatrics.

www.downsymptoms.com