YY syndrome

YY syndrome is a rare genetic disorder that affects males. It is characterized by the presence of an extra Y chromosome in each of a male's cells. Normal males have one X and one Y chromosome. However, males with YY syndrome have one X and two Y chromosomes, making their karyotype XYY.

Causes

YY syndrome is not inherited; it occurs as a random event during the formation of sperm cells in the father. An error in cell division called nondisjunction can result in sperm cells with an extra copy of the Y chromosome. If one of these atypical sperm cells contributes to the genetic makeup of a child, the child will have an extra Y chromosome in each of the body's cells.

Symptoms

Males with YY syndrome are usually taller than average and may have severe acne during adolescence. They are more likely than other males to have learning disabilities and delayed speech and language development. Some males with the condition have minor physical differences, such as an unusually large nose, an unusually round face, and flat feet. However, many males with YY syndrome do not have any physical or intellectual differences.

Diagnosis

YY syndrome is usually diagnosed by a genetic test called a karyotype. This test examines a person's chromosomes in a sample of blood. If the karyotype reveals an extra Y chromosome, the diagnosis is YY syndrome.

Treatment

There is no cure for YY syndrome, but treatments can help manage symptoms. For example, speech therapy can help with language development, and special education services can assist with learning disabilities. Medication can also be used to manage severe acne.

Prognosis

The prognosis for males with YY syndrome is generally good. Most are able to live normal, healthy lives with the condition. However, they may need support to manage learning disabilities and other symptoms.

See also

• Klinefelter syndrome
• Turner syndrome
• Triple X syndrome

YY syndrome Resources
Need Help Finding a Doctor? WikiMD's DocFinder can help find general and specialist physicians.	Latest articles Most recent articles Ongoing trials.