Down syndrome

The definition of down syndrome is a chromosomal disorder also known as trisomy 21 or trisomy G which is caused by a partial or full extra 21st chromosome.

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.