Facts About Down Syndrome
- The extra chromosome often causes some level of mental retardation and is the number one cause of human birth defects
- Down syndrome affects one out of every 660 births.
- Older couples are more likely to produce offspring with the condition.
- Down syndrome is typically the product of a mistake in cell division at the time of conception, resulting in an embryo with a third copy of the 21st chromosome, instead of the typical two copies.
- Down syndrome can be diagnosed before or after birth.
- Common symptoms in children include slowed movement, reduced fertility, difficulty with speech, hearing loss, smaller heads with flat faces, short stature.
An example of down syndrome is a baby born with an extra chromosome.
Origin of Down syndromeafter J. L. H. Down (1828-96), British physician
or Down's syndrome
Origin of Down syndromeAfter John Langdon Haydon Down, (1828–1896), British physician.
Known only as Down's syndrome in the UK.
Named after John L.H. Langdon-Down (1828-1896), an English physician who described it in the late 1800s. The term was first used in 1961.