Trisomy 13, also called Patau syndrome, is a genetic disorder associated with the presence of extra material from chromosome 13.
Trisomy 13 occurs when extra DNA from chromosome 13 appears in some or all of the body's cells.
The extra material interferes with normal development.
Trisomy 13 occurs in about 1 out of every 10,000 newborns. Most cases are not passed down through families (inherited). Instead, the events that lead to Trisomy 13 occur in either the sperm or the egg that forms the fetus.