Down Syndrome

• Down Syndrome Introduction
• The Genetics of Down Syndrome - Trisomy 21
• The Effects of Trisomy 21 - Symptoms of Down Syndrome
• Characteristic Features of Down Syndrome
• Down Syndrome Treatment
• Screening for Down Syndrome
• For More Information
• Web Links
• Synonyms and Keywords
• Authors and Editors
• Related down syndrome article:
  Down Syndrome - on MedicineNet
  

Down Syndrome Introduction

Down syndrome was first described in 1866. The cause of Down syndrome (trisomy 21) was discovered in 1959. Down syndrome is relatively well known, with distinctive characteristics such as mental retardation, distinguishing facial features, and other traits. In the United States, Down syndrome occurs in 1 in 800 live births, and approximately 6000 children are born with Down syndrome each year. About 85% of infants with Down syndrome survive 1 year, and 50% of people with Down syndrome live longer than 50 years.