Down Syndrome Awareness: National Association For Down Syndrome (NADS.org)
Down syndrome is a genetic condition that causes delays in physical and intellectual development. It occurs in 1 in every 792 live births. Individuals with Down syndrome have 47 chromosomes instead of the usual 46.
Initially the diagnosis is based on physical characteristics that are commonly seen in babies with Down syndrome. These include low muscle tone, a single crease across the palm of the hand, a slightly flattened facial profile and an upward slant to the eyes. The diagnosis must be confirmed by a chromosome study (karyotype). This additional genetic material alters the course of development and causes the characteristics associated with the syndrome.
There are three chromosomal patterns that result in Down syndrome:
- Trisomy 21 (nondisjunction): caused by a faulty cell division that results in having three #21 chromosomes instead of two.
- Translocation: A part of chromosome #21 breaks off during cell division and attaches to another chromosome. It accounts for approximately 3.5 percent of all cases.
- Mosaicism occurs when nondisjunction of chromosome #21 takes place in one of the initial cell divisions after fertilization. The result a mixture of cells, containing 46 or 47 chromosomes. This occurs in approximately 1.5 percent of all cases.
Down syndrome is not related to race, nationality, religion or socioeconomic status. The most important fact to know about individuals with Down syndrome is that they are more like others than they are different.
New Jersey Down Syndrome Groups
Bringing Up Down Syndrome
Down Syndrome Association of Central New Jersey
Jersey Shore Down Syndrome Association
(Atlantic/Cape May Counties)