Down syndrome is a chromosomal condition that occurs in approximately one in every 700 births, making it one of the most common chromosomal conditions. Down syndrome occurs across all civilizations, ethnic groups, socioeconomic levels, and geographic regions.
Genetic Basis
In every cell in the human body, there is a nucleus where genetic material is stored in genes. Genes carry the codes responsible for all of our inherited traits and are grouped on structures called chromosomes. Typically, the nucleus of each cell contains 23 pairs of chromosomes. Down syndrome occurs when an individual has a full or partial extra copy of chromosome 21.
Common Physical Characteristics
People with Down syndrome share some or all of the following physical characteristics:
- General low muscle tone and ligament laxity (hypotonia)
- Short stature
- Upward and outward slanting of the eyes
- A single deep crease across the center of the palm
Each person with Down syndrome may exhibit all, some, or none of these features to varying degrees.
Cognitive Abilities and Daily Life
People with Down syndrome experience cognitive delays that range from mild to moderate. It is not possible to predict in advance a person's individual strengths and abilities. People with Down syndrome are able to sit, walk, talk, play, and participate in most other activities.
The Role of Support and Environment
The quality of educational programs, a stimulating home environment, good healthcare, and positive support from family, friends, and the community help people with Down syndrome develop their abilities to their fullest potential and lead fulfilling, achievement-filled lives. People with Down syndrome can attend school, work, participate in decisions that affect them, and contribute to their communities in many wonderful ways.
Source: The information in this article has been reproduced under an exclusive agreement with the National Down Syndrome Society. Available at: ndss.org
