Trisomy 21 (Down Syndrome)

Trisomy 21, known as Down syndrome, is a genetic disorder resulting from genetic errors on the 21st chromosome. Down syndrome causes a range of intellectual impairments and developmental delays as well as health conditions.

Down syndrome is the most common Trisomy. Although most trisomies are due to random errors, mothers over 35 years of age have an increased risk of having a child with Down syndrome. Down syndrome occurs in approximately 1 in 700 live births, or about 6,000 babies every year.

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About Down Syndrome

Impact on Development

Some children will have three copies of chromosome 21 in all of their cells (Trisomy 21) while others have three copies in only some of their cells (mosaic Down syndrome) or extra parts of chromosome 21 attached to another chromosome (Translocation Down syndrome). The severity of the impact of Trisomy 21 on development will depend upon the number of cells affected.

Children with Down syndrome have distinctive facial features such as a flattened face, a short neck, almond-shaped eyes, and a small mouth with a tongue that appears to stick out. Most will have mild to moderate developmental and intellectual disabilities, although children with Down syndrome will vary considerably in their abilities.

Trisomy 21 is also associated with other health problems. Children with Down syndrome are at an increased risk for having heart defects, digestive problems such as gastroesophageal reflux or celiac disease, and hearing and vision problems. They may also have problems with their thyroid and have increased risk for leukemia or infections.

Clinical Course and Life Expectancy

Children with Down syndrome often have low muscle tone at birth and may experience life-threatening medical conditions, such as those associated with heart defects. Unlike other Trisomy disorders, most children with Down syndrome will live into adulthood. Individuals with Down syndrome with fewer or well-managed health problems can expect to live to be 60 years of age or more.

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Treatment Options

There is no cure for Down syndrome; however, most individuals can live happy, productive lives. Medical conditions such as heart defects may require surgical correction or management with medication. Therapeutic services, such as speech, occupational, and physical therapy, should be provided as soon as possible to children with Down syndrome to assist their development. Early Intervention services received in infancy will ensure that families have the support needed to promote their child’s development and health and improve their physical and intellectual abilities.

Down Syndrome Resources

Resources for Families

The National Down Syndrome Congress (NDSC)
The NDSC is committed to building a sense of community among all those concerned with Down syndrome. The National Down Syndrome Congress offers information on any subject related to Down syndrome. It also maintains a directory to promote parent-to-parent and parent-to-professional networking. Call 1-800-232-6372 for more information.

Support Services

Down Syndrome Diagnosis Network connects, supports, and provides accurate information to parents and medical professionals.
The Arc of Mississippi is a grassroots advocacy organization for citizens of all ages with cognitive, intellectual and developmental disabilities, and their families. The Arc promotes the welfare and full inclusion of individuals with intellectual and developmental disabilities and provides family support and advocacy.
Mississippi Society for Disabilities supports the needs of Mississippi's disabled/special needs community through innovative approaches.
The Mississippi Division of Medicaid provides access to health coverage for children with disabilities

Resource Centers or Clearinghouses

Down Syndrome Resource Foundation (DSRF) offers educational and health opportunities to children and young adults with Down syndrome. Their programs are based on the latest intervention research and best practice and adapted for individual learner's needs.

National and Local Organizations

National Down Syndrome Society supports and advocates for the Down syndrome community by providing resources, policy, and community engagement.
Central Mississippi Down Syndrome Society promotes health, awareness and acceptance of Mississippians with Down syndrome. CMDSS provides support services for parents of children with Down syndrome.
Gulf Coast Down Syndrome Society is a network of families and individuals with Down syndrome who promote inclusion of individuals with Down syndrome.

Education and Support Programs

MSDH's Children and Youth with Special Health Care Needs (CYSHCN) program offers Care Coordination services for children with special healthcare needs from birth through twenty-one years of age.
MSDH's First Steps Early Intervention program offers services and supports according to an Individualized Family Service Plan for infants and toddlers with developmental delays.
MSDH's Healthy Moms, Healthy Babies program offers case management, enhanced access to health care, nutritional and psychosocial support, home visits, and health education for high-risk pregnant women and their babies less than one year old.
PACER provides individual assistance, workshops, publications, and other resources to help families make decisions about education and other services for their child or young adult with disabilities.