Usage examples (35)

• Down syndrome, also called trisomy 21, is a genetic disorder first reported in 1866 by J. Langdon Down, a British physician.
• Alzheimer's disease patients harbor some cells with three copies of chromosome 21, known as trisomy 21, instead of the usual two.
• BPMC is the sole owner of a patent related to non-invasive prenatal screening for fetal abnormalities such as trisomy 21 Down Syndrome.
• It is also known as trisomy 21.