What is the deficiency associated with Hemophilia A?

Hemophilia A is characterized by a deficiency of Factor VIII, which plays a crucial role in the blood coagulation cascade. Factor VIII is involved in the intrinsic pathway of hemostasis, and its absence leads to impaired thrombin formation and reduced fibrin clot formation. This deficiency manifests clinically in patients who often experience prolonged bleeding episodes, easy bruising, and, in severe cases, spontaneous bleeding into joints and muscles.

The genetic basis of Hemophilia A is typically an X-linked recessive mutation affecting the gene responsible for producing Factor VIII. Since this condition primarily affects males, females can be carriers, passing the gene mutation on to their male offspring, who may then manifest the condition.

Understanding the nature of the Factor VIII deficiency helps in managing the condition with therapies that include replacement of the missing factor, which can significantly improve hemostasis in affected individuals.