Haemophilia is an X-linked recessive condition that impairs the body’s ability to control blood clotting

  • It is more common in males than females (as males are hemizygous and have only one X chromosome)

People with haemophilia (haemophiliacs) have lower levels of functional clotting factors in their blood plasma

  • This means the normal coagulation cascade is impaired and fibrin formation does not occur
  • Thus while a temporary scab may form (due to the formation of a platelet plug), a lasting blood clot cannot form

Haemophiliacs can die from minor injuries, as the continued loss of blood flow cannot be prevented via clot formation

  • There are different types of haemophilia with varying severities, depending on which specific clotting factor is defective
  • Haemophilia A (clotting factor XIII deficiency) is more common than haemophilia B (clotting factor IX deficiency)

Cause of Haemophilia