Question

Which sex chromosome aneuploidy affects males with an extra Y chromosome?

Options

• Klinefelter's Syndrome (47, XXY)

• XYY Syndrome (47, XYY)

• Triple X Syndrome (47, XXX)

• Turner's Syndrome (45, XO)

Answer 1

XYY Syndrome (47, XYY) results from an extra Y chromosome in males. The incidence is approximately 1 in 1,000 male newborns. Affected individuals are phenotypically normal males with tall stature who remain fertile in most cases. Historical literature associated this condition with behavioral tendencies, but this is no longer considered clinically significant.