Haemophilia A is a genetic disorder that results in abnormal bleeding due to a deficiency in clotting factor VIII. This deficiency impairs the blood's ability to clot properly, which can lead to prolonged bleeding episodes, especially after injury or surgery. Haemophilia A is also known as classical haemophilia or factor VIII deficiency.

Factor-VIII and its role in clotting

Factor-VIII is a protein that plays a critical role in the blood clotting process. It is one of several clotting factors that work together to form a clot and stop bleeding. Factor-VIII is produced in the liver and circulates in the bloodstream in an inactive form until it is needed. When an injury occurs and bleeding begins, the inactive factor-VIII is activated and becomes part of the clotting cascade, which ultimately forms a stable clot.

Haemophilia A and its inheritance

Haemophilia A is an X-linked recessive disorder, which means it is caused by mutations in the F8 gene on the X chromosome. Since females have two X chromosomes and males have one X and one Y chromosome, haemophilia A is more commonly seen in males. Females can be carriers of the disorder and can pass the faulty gene to their offspring.

Symptoms and treatment of haemophilia A

The symptoms of haemophilia A can vary depending on the severity of the clotting factor deficiency. Mild cases may not cause any symptoms, while severe cases can result in spontaneous bleeding episodes, joint damage, and other complications. Treatment for haemophilia A typically involves replacement therapy with clotting factor VIII, which can be administered on a regular basis or as needed to control bleeding episodes. In some cases, gene therapy may also be used to correct the underlying genetic defect.