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.
Apr 19, 2014 ... 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 ...
Down syndrome is caused by a random error in cell division that results in the
presence of an extra copy of chromosome 21. The type of error is called ...
Down syndrome, also known as trisomy 21, is a genetic disorder. Down
syndrome is caused by an extra copy of ...
Aug 22, 2016 ... Down syndrome is a condition caused by chromosome replication errors. A baby
born with Down syndrome may have symptoms such as ...
Down syndrome is a lifelong condition in which a person is born with distinct
physical features and some degree of cognitive disability.
This additional genetic material alters the course of development and causes the
characteristics associated with Down syndrome. A few of the common physical ...
Oct 28, 2015 ... Down syndrome is the most common genetic condition in the United States. It
causes physical and mental developmental delays and disabilities.
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.