Edwards Syndrome, also known as Trisomy 18, is a chromosomal condition that is associated with many abnormalities in the body due to one extra chromosome #18 (as seen in the box on the karyotype).
Website Image (IUPUI Department of Biology, Human Chromosomal Disorders, April 30, 2003): [karyotype of a human cell with an extra chromosome on chromosome #18]. Retrieved April 16, 2015 from http://www.biology.iupui.edu/biocourses/N100/2k2humancsomaldisorders.html