XX male syndrome; de la Chapelle syndrome

Epidemiology

• rare

Genetics

• caused by unequal crossing over between X & Y chromosomes during meiosis in the father, resulting in the X chromosome containing the normally-male SRY gene

Clinical manifestations

• small testes
• patients are invariably sterile
• facial hair growth is usually poor
• libido is diminished
• feminine characteristics variable
• varying degrees of gynecomastia
• no intra-abdominal Mullerian tissue

Complications

• cryptorchidism
• hypospadias
• ambiguous genitalia
• short stature

Management

• testosterone generally needed at puberty for full development of male characteristics

More general terms

• genetic syndrome (multisystem disorder)

Additional terms

• Klinefelter's syndrome