Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome.
Down syndrome varies in severity among individuals, causing lifelong intellectual disability and developmental delays. It's the most common genetic chromosomal disorder and cause of learning disabilities in children. It also commonly causes other medical abnormalities, including heart and gastrointestinal disorders.
Better understanding of Down syndrome and early interventions can greatly increase the quality of life for children and adults with this disorder and help them live fulfilling lives.
June 27, 2017
- What is Down syndrome? National Down Syndrome Society. http://www.ndss.org/down-syndrome/what-is-down-syndrome/. Accessed Dec. 16, 2016.
- Down syndrome fact sheet. National Down Syndrome Society. http://www.ndss.org/Down-Syndrome/Down-Syndrome-Facts/. Accessed Dec. 16, 2016.
- Messerlian GM, et al. Down syndrome: Overview of prenatal screening. http://www.uptodate.com/home. Accessed Dec. 16, 2016.
- National Library of Medicine. Down syndrome. Genetics Home Reference. https://ghr.nlm.nih.gov/condition/down-syndrome. Accessed Dec. 16, 2016.
- Facts about Down syndrome. Centers for Disease Control and Prevention. https://www.cdc.gov/ncbddd/birthdefects/downsyndrome.html. Accessed Dec. 16, 2016.
- Down syndrome. Eunice Kennedy Shriver National Institute of Child Health and Human Development. https://www.nichd.nih.gov/health/topics/down/conditioninfo/Pages/default.aspx. Accessed Dec. 16, 2016.
- Frequently asked questions. Prenatal genetic diagnostic tests. FAQ164. Pregnancy. American College of Obstetricians and Gynecologists. https://www.acog.org/-/media/For-Patients/faq164.pdf?dmc=1&ts=20161216T1208042192. Accessed Dec. 16, 2016.
- Ostermaier KK. Down syndrome: Management. http://www.uptodate.com/home. Accessed Dec. 22, 2016.
- Ostermaier KK. Down syndrome: Clinical features and diagnosis. http://www.uptodate.com/home. Accessed Jan. 10, 2017.
- Gabbe SG, et al., eds. Genetic screening and prenatal genetic diagnosis. In: Obstetrics: Normal and Problem Pregnancies. 7th ed. Philadelphia, Pa.: Saunders Elsevier; 2017.
- Rink BD, et al. Screening for fetal aneuploidy. Seminars in Perinatology. 2016;40:35.
- Bunt CW, et al. The role of the family physician in the care of children with Down syndrome. American Family Physician. 2014;90:851.
- Butler Tobah YS (expert opinion). Mayo Clinic, Rochester, Minn. Jan. 26, 2017.