<Tr> <Th> Prognosis </Th> <Td> Good </Td> </Tr> <Tr> <Th> Frequency </Th> <Td> ~ 1 in 1,000 males </Td> </Tr> <P> 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 . </P> <P> The condition is generally not inherited from a person's parents but rather occurs as a result of a random event during sperm cell development . Diagnosis is by a chromosomal analysis . There are 47 chromosomes, instead of the usual 46, giving a 47, XYY karyotype . </P>

Recent studies suggest that xyy males tend to be
find me the text answering this question