This condition occurs in about 1 in 1,000 newborn boys. Five to 10 boys with 47,XYY syndrome are born in the United States each day. Many affected males are never diagnosed or not diagnosed until later in life.XYY syndrome is a genetic condition in which a male has an extra Y chromosome .  Symptoms are usually few.  They may include being taller than average, acne , and an increased risk of learning problems .   The person is generally otherwise normal, including normal fertility .