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Down syndrome is a genetic disorder caused when abnormal cell division results in extra genetic material from chromosome 21. Down syndrome varies in severity and causes lifelong intellectual disability and developmental delays. It also causes health problems to some people.

A few of the common physical traits of Down Syndrome include low muscle tone, small stature, an upward slant in the eyes, and a single deep crease across the center of the palm. However, individuals with Down syndrome may possess these characteristics to different degrees or not at all.

Down syndrome is the most common genetic disorder and cause of learning disabilities in children, with one in every 691 babies in the US being born with it. Approximately 400,000 Americans have Down syndrome and 6,000 are born with it in the US each year.

There are three different types of Down syndrome. Trisomy 21 (nondisjunction) accounts for 95% of cases, and results in an embryo with three copies of chromosome 21 instead of the usual two. Mosaicism (mosaic Down syndrome) accounts for only 1% of all cases, and is diagnosed when there is a mixture of two types of cells. Some contain the usual 46 chromosomes and some contain 47, while those cells with 47 chromosomes contain and extra chromosome 21. Translocation accounts for about 4% of all cases. In translocation, the total number of chromosomes in the cells remains 46. However, an additional full or partial copy of chromosome 21 attaches to another chromosome, usually chromosome 14. This presence causes the characteristics of Down syndrome.

Older women have an increased chance of having a child with Down syndrome. A 35-year-old woman has about a one in 350 chance of conceiving a child with Down Syndrome. The chances increase to one in 100 by age 40, and one in 30 by age 45, though the age of the mother does not seem to be linked to the risk of translocation. All three types of Down syndrome are genetic conditions, but only 1% of all cases have a hereditary component. While hereditary is not a factor in trisomy 21 and mosaicism, there is a hereditary component resulting from a translocation in a third of cases of down syndrome.

Sources: National Down Syndrome Society ( and Mayo Clinic (


Special Olympics athlete Patrick Sallarulo gives words of encouragement to others with Down syndrome (42 sec):

Click here for the full interview


Down Syndrome Resources

The Global Down Syndrome Foundation is a non-profit 501 (c)(3) dedicated to significantly improving the lives or people with Down syndrome through research, medical care, education, and advocacy. Global was established in 2009, and created and organizes the Be Beautiful Be Yourself Fashion Show, which is the single-largest fundraiser benefiting people with Down Syndrome. They also organize and fund many programs, conferences, and grants.

The Jerome Lejeune Foundation was established in 1996 as a family foundation in the Lejeune family home, two years after the death of legendary geneticist Jerome Lejeune. All contributions received are directly applied to serve those with Down syndrome and other genetic intellectual disabilities through research, care and advocacy. Their Call for Grants typically provide funding to support fundamental research that is directed toward furthering an understanding of the biological mechanisms and metabolic imbalance resulting from trisomy 21 and other genetic anomalies.


The Down Syndrome Foundation supports the Down Syndrome Camp, and offers a unique and safe environment here individuals with Down syndrome (ages 10-21) can cultivate friendships, discover new abilities and talents, develop an increase in self-worth, and have the unforgettable life-changing experience of overnight camp.


The National Down Syndrome Society (NDSS) gained nonprofit status in 1979, and began its ongoing work to increase general public awareness and acceptance of people with Down syndrome. In December of 2014, their ABLE Act (Achieving a Better Life Experience) was passed in Congress and signed into law. The ABLE Act helps individuals with Down syndrome live full, productive lives in their communities without losing benefits provided through private insurances, the Medicaid program, the supplemental security income program, the beneficiary’s employment, and other sources.


The National Association for Down Syndrome (NADS) was founded in Chicago in 1961, making it the oldest organization in the country serving individuals with Down syndrome. The NADS provides family support, resource referrals, public awareness, self-advocate programs, retreats, seminars, and publics speakers for schools and organizations.


The National Down Syndrome Congress (NDSC) is a membership-sustained not-for-profit organization founded in 1973, and dedicated to an improved world for individuals with Down syndrome. NDSC promotes the interests of people with Down syndrome and their families through advocacy, public awareness, and information.

The Down Syndrome Association of Central Florida is a not-for-profit association founded in 1991 for parents of children with Down syndrome. Their resources are designed to help parents get the information and support needed to address the specific joys and challenges of raising a child with Down syndrome.

Down Syndrome International (DSi) is a UK based international charity, comprising a membership of individuals and organizations from all over the world, committed to improving quality of life for people with Down syndrome worldwide by providing information, representing people with Down syndrome, and raising awareness about Down syndrome.

Down Syndrome Education USA is a US-based charity that transforms the lives of young people with Down syndrome through particular education and effective support. They provide research strategies focusing on human development and cognitive research, publish books and teaching materials that offer practical guidance for parents and teachers, and regularly present conferences and webinars.


The Down Syndrome Foundation of Florida is a non-profit organization made up of volunteers with the belief that through creative programs and partnerships, they can facilitate opportunities and experiences to rid misunderstandings of Down syndrome. They facilitate projects that enhance the welfare, education, health, and artistic and athletic abilities of individuals with Down syndrome.


The Down Syndrome Information Alliance are a non-profit organization consisting of volunteers, donors, and families. The organization provides support and resources to help empower individuals with Down syndrome, their families, and the community through events, programs, and resources.