Final answer:
Hemophilia A is a genetic disorder caused by a lack of clotting factor VIII. It is an X-linked recessive disorder, more common in males, and passed from carrier females. The condition leads to excessive bleeding from minor injuries and requires treatment with clotting factor infusions.
Step-by-step explanation:
Hemophilia A is caused by a deficiency in clotting factor VIII, which is critical for the blood-clotting process. It is an X-linked recessive genetic disorder, meaning it is associated with the X chromosome. Females have two X chromosomes (XX), so they would need to inherit the defective gene from both parents to manifest the disease. Males, having only one X chromosome (XY), need only one defective gene to exhibit hemophilia. Therefore, this disorder commonly affects males and is passed on from carrier females, who usually do not exhibit symptoms.
Rarely, the disorder can occur due to a new mutation. Due to the nature of X-linked inheritance, hemophilia A is much more common in males than in females. Hemophilia patients often experience bleeding from minor injuries and complications such as bleeding into joints. Treatments include infusions of the lacking clotting factors and may in the future involve genetic therapy to address the underlying cause of the deficiency.