Question

Name the genetic disorder caused by an extra X-chromosome in a human male. State the diagnostic features of the individual suffering from it.

Answer 1

Klinefelter’s syndrome is a genetic disorder characterized by the presence of an extra X chromosome (47, XXY). Individuals with this condition appear phenotypically male but have underdeveloped testes and sparse body hair. They are typically sterile and often have some degree of mental impairment. Physically, they may have longer limbs and some breast development. Overall, they appear fairly normal but are sterile males with underdeveloped genitalia and reduced secondary sexual characteristics.