** Down syndrome occurs when an individual has three, rather than two, copies of the 21st chromosome. This additional genetic material alters the course of development and causes the characteristics associated with Down syndrome.

** There are more than 400,000 people living with Down syndrome in the United States. One in every 733 babies is born with Down syndrome.

**The incidence of births of children with Down syndrome increases with the age of the mother. But due to higher fertility rates in younger women, 80% of children with Down syndrome are born to women under 35 years of age.

** Life expectancy for people with Down syndrome has increased dramatically in recent decades - from 25 in 1983 to 60 today.