Definition of Trisomy 18:
Trisomy 18 is a genetic disorder associated with the presence of extra material from chromosome 18.
Causes, incidence, and risk factors:
Trisomy 18 is a relatively common syndrome affecting approximately 1 out of 3,000 live births. It is three times more common in girls than boys. The syndrome is caused by the presence of an extra material from chromosome 18. The extra material interferes with normal development.
