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Facts about Down Syndrome

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  • Down syndrome is named after the British doctor John Langdon Down, who was the first to describe characteristics of people with Down syndrome in 1866.
  • Down syndrome, or Trisomy 21, is a condition whereby there are three copies of the 21st chromosome instead of two.
  • Down syndrome is one of the leading clinical causes of cognitive delay in the world – it is not related to race, nationality, religion or socio-economic status.
  • Down syndrome is the most frequently occurring chromosomal condition, affecting approximately 1 in every 733 births in the United States.
  • More than 400,000 people in the U.S. and an estimated 6,000 people in Colorado have Down syndrome. It is estimated that 5 million people worldwide have Down syndrome.
  • Down syndrome probability increases with advanced age in mothers; however, 80 percent of children who have Down syndrome are born to mothers under the age of 35.
  • Twenty years ago, the life expectancy of someone affected by Down syndrome was 20 years old. Today the life expectancy is approximately 55 years of age and increasing.
  • 30-50% of all children born with Down syndrome will have a congenital heart defect and upward of 50% will experience the early onset of Alzheimer’s.
  • Children with Down syndrome can read and are gifted visual learners.  They have a predisposition to specific learning strengths and challenges that are not currently addressed in practice in special education.
  • Improvements in care over the past 15 years have led to a 20-point increase in IQ for individuals with Down syndrome.
  • Despite the frequency, Down syndrome is the least funded of the conditions serviced by the National Institutes of Health receiving approximately $17 million out of a total $28 billion budget. 
  • It is extremely rare for a person with Down syndrome to develop a hard tumor cancer, to have a heart attack, or to suffer a stroke.