Down Syndrome Facts, Myths & Truths

This information is courtesy of the National Down Syndrome Society. Find more valuable resources on their website at ndss.org.

♦ Down syndrome occurs when an individual has a full or partial extra copy of chromosome 21. This additional genetic material alters the course of development and causes the characteristics associated with Down syndrome.

♦ There are three types of Down syndrome: trisomy 21 (nondisjunction) accounts for 95% of cases, translocation accounts for about 4% and mosaicism accounts for about 1%.

♦ Down syndrome is the most commonly occurring chromosomal condition. One in every 691 babies in the United States is born with Down syndrome.

♦ There are more than 400,000 people living with Down syndrome in the United States.

♦ Down syndrome occurs in people of all races and economic levels.

♦ The incidence of births of children with Down syndrome increases with the age of the mother. But due to higher fertility rates in younger women, 80% of children with Down syndrome are born to women under 35 years of age.

♦ People with Down syndrome have an increased risk for certain medical conditions such as congenital heart defects, respiratory and hearing problems, Alzheimer's disease, childhood leukemia, and thyroid conditions. Many of these conditions are now treatable, so most people with Down syndrome lead healthy lives.

♦ A few of the common physical traits of Down syndrome are low muscle tone, small stature, an upward slant to the eyes, and a single deep crease across the center of the palm. Every person with Down syndrome is a unique individual and may possess these characteristics to different degrees or not at all.

♦ Life expectancy for people with Down syndrome has increased dramatically in recent decades - from 25 in 1983 to 60 today.

♦ People with Down syndrome attend school, work, participate in decisions that affect them, and contribute to society in many wonderful ways.

♦ All people with Down syndrome experience cognitive delays, but the effect is usually mild to moderate and is not indicative of the many strengths and talents that each individual possesses.

♦ Quality educational programs, a stimulating home environment, good health care, and positive support from family, friends and the community enable people with Down syndrome to develop their full potential and lead fulfilling lives.


  • If you are a new or expectant parent or guardian of a child with Down syndrome and aren't sure where to begin your learning, this page will guide you towards resources and community connections to help you along your journey


Down Syndrome Myths & Truths

MYTH: Down syndrome is a rare disorder.

TRUTH: Down syndrome is the most commonly occurring genetic condition. One in every 691 babies in the United States is born with Down syndrome, or approximately 6,000 births per year. Today, there are more than 400,000 people with Down syndrome living in the United States. 

MYTH: People with Down syndrome have a short life span. 

TRUTH: Life expectancy for individuals with Down syndrome has increased dramatically in recent years, with the average life expectancy approaching that of peers without Down syndrome.

MYTH: Down syndrome is hereditary and runs in families.  

TRUTH: Down syndrome is hereditary in approximately 1% of all instances.  In the other 99% of cases Down syndrome is completely random and the only known factor that increases the risk is the age of the mother (over 35).  Translocation is the only type of Down syndrome known to have hereditary link.  Translocation accounts for 3 to 4% of all cases of Down syndrome.  Of those, one third (or 1% of all cases of Down syndrome) are hereditary.  

MYTH: Most children with Down syndrome are born to older parents.

TRUTH: Most children with Down syndrome are born to women younger than 35 years old simply because younger women have more children. However, the incidence of births of children with Down syndrome increases with the age of the mother.

MYTH: People with Down syndrome have severe cognitive delays.

TRUTH: Most people with Down syndrome have cognitive delays that are mild to moderate. Children with Down syndrome fully participate in public and private educational programs. Educators and researchers are still discovering the full educational potential of people with Down syndrome.

MYTH: Most people with Down syndrome are institutionalized.

TRUTH: Today people with Down syndrome live at home with their families and are active participants in the educational, vocational, social, and recreational activities of the community. They are integrated into the regular education system and take part in sports, camping, music, art programs and all the other activities of their communities. People with Down syndrome are valued members of their families and their communities, contributing to society in a variety of ways.

MYTH: Parents will not find community support in bringing up their child with Down syndrome.

TRUTH: In almost every community of the United States there are parent support groups and other community organizations directly involved in providing services to families of individuals with Down syndrome. 

MYTH: Children with Down syndrome must be placed in segregated special education programs.

TRUTH: Children with Down syndrome have been included in regular academic classrooms in schools across the country. In some instances they are integrated into specific courses, while in other situations students are fully included in the regular classroom for all subjects. The current trend in education is for full inclusion in the social and educational life of the community. Increasingly, individuals with Down syndrome graduate from high school with regular diplomas, participate in post-secondary academic and college experiences and, in some cases, receive college degrees.

MYTH: Adults with Down syndrome are unemployable.

TRUTH: Businesses are seeking adults with Down syndrome for a variety of positions. They are being employed in small- and medium-sized offices: by banks, corporations, nursing homes, hotels and restaurants. They work in the music and entertainment industry, in clerical positions, childcare, the sports field and in the computer industry to name a few.

MYTH: People with Down syndrome are always happy.

TRUTH: People with Down syndrome have feelings just like everyone else in the population. They experience the full range of emotions. They respond to positive expressions of friendship and they are hurt and upset by inconsiderate behavior.

MYTH: Adults with Down syndrome are unable to form close interpersonal relationships leading to marriage.

TRUTH: People with Down syndrome have meaningful friendships, date, socialize, form ongoing relationships and marry.

MYTH: Down syndrome can never be cured.

TRUTH: Research on Down syndrome is making great strides in identifying the genes on chromosome 21 that cause the characteristics of Down syndrome. Scientists now feel strongly that it will be possible to improve, correct or prevent many of the problems associated with Down syndrome in the future.