Down syndrome (DS or DNS), also known as trisomy 21, is a genetic disorder
caused by the presence of all, or part of a third copy of chromosome 21.
About 95 percent of the time, Down syndrome is caused by trisomy 21 — the
child has three copies of chromosome 21 (instead of the usual two copies) in all ...
Apr 22, 2016 ... Down syndrome (or Down's syndrome) is a chromosomal disorder caused by an
error in cell division that results in an extra 21st chromosome.
Jun 11, 2015 ... Read about Down syndrome facts, symptoms, tests, statistics, treatment, and ...
Read more about Down syndrome causes and symptoms » ...
Oct 28, 2015 ... Down syndrome is the most common genetic condition in the United States. It
causes physical and mental developmental delays and ...
Down syndrome is a developmental disorder caused by an extra copy of
chromosome 21 (which is why the disorder is also called "trisomy 21"). Having an
Down syndrome is a condition in which extra genetic material causes delays in
the way a child develops, both physically and mentally.
A century after Down syndrome was first described, scientists discovered that the
root cause of this disorder is a condition called trisomy 21. What strides in ...
Down syndrome aka trisomy 21 is the most common birth defect in the United
States. Learn more about the causes, symptoms and risks of Down Syndrome.
Mar 3, 2016 ... Down syndrome is also referred to as Trisomy 21. This extra copy changes how
the baby's body and brain develop, which can cause both ...