Down syndrome

Down syndrome is a genetic disorder of our body's chromosomes. Most people have a total of 46 chromosomes. People with Down syndrome have a total of 47. Down syndrome results from changes in the genetic material that creates the chromosomes and is the most common disorder of human chromosomes. It is usually diagnosed shortly after birth.

The diagnosis is usually based on physical features. Eyes often have a slant to the openings and extra skin at the middle corner. The mouth tends to stay open with the tongue sticking out. Muscle tone is usually low, making the arms and legs more relaxed. People diagnosed with Down syndrome are mentally disabled. Many people also have heart defects and other disorders.

The chance of having a baby with Down syndrome rises, as parents get older. It depends more on the mother's age than the father's. The chance of having a baby with Down syndrome goes up quickly when the mother is over 34 years. It also goes up when the father is over 60 years of age. This suggests that the main cause of the disorder is the aging of egg cells. Rarer causes of Down syndrome are heredity or long term exposures to radiation or viruses.

A young mother who has one child with Down syndrome has about a 2 in 100 chance of having another. An older mother will continue to have about the same chance for her age.

Down syndrome is not curable. It affects the mental capabilities of a child. The growth and development of a child with Down syndrome should not be compared with other children. Special growth and development guidelines exist for children with Down syndrome. These children will lag in their mental development but they are often very social and pleasant. People with Down syndrome may have defects in the heart, intestines, pelvic bone, and thyroid. They tend to have frequent respiratory infections. They also have an increased risk of leukemia.

Down syndrome has no cure. Surgery to correct defects and better therapy for infections has increased the usual life span. Many children with Down syndrome are cared for at home and attend special education classes. Many participate in group activities such as the Special Olympics. As a child with Down syndrome becomes older, the parents will need to make many decisions regarding medical care, education, and living arrangements.

Parents of a baby with Down syndrome may require support in meeting their child's needs. The family may benefit from counseling to set realistic goals for the child and balance the needs of other family members.

If you have concerns about your risk of having a child with Down syndrome, consult your healthcare provider about prenatal testing.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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