what is Down syndrome

Down syndrome is the most frequently occurring chromosomal abnormality and affects people of all races, cultures, and economic levels. Down syndrome occurs as a result of extra genetic material, namely an extra copy of chromosome 21. Whereas a typical person (without Trisomy 21) has two copies of all chromosomes (totaling 46), those with Down syndrome have 47 chromosomes as a result of that triplication. The term “Down syndrome” is named after John Langdon Down, the British physician who described the syndrome in 1866.

The condition is characterized by a combination of major and minor differences in structure. Often Down syndrome is associated with some impairment of cognitive ability and physical growth, and a particular set of facial characteristics. Individuals born with Down syndrome are at a higher risk for multiple health problems, such as congenital heart defects, visual & hearing impairments, respiratory problems, obstructed digestive systems, sleep apnea, and susceptibility to infection. Most will also have some level of intellectual and/or adaptive disability, usually in the mild to moderate range.

Today, with early intervention, advanced medical care, better education and greater social acceptance, people with Down syndrome live full, productive lives and have a life expectancy of 55 years and beyond.