Haemophilia + related disorders

Question 1

Define haemostasis

Answer 1

arrest of bleeding

Question 2

Haemophilia A is caused by a deficiency in which factor?

Answer 2

Factor VIII (8) deficiency

Question 3

Haemophilia B is caused by a deficiency in which factor?

Answer 3

Factor IX (9) deficiency

Question 4

Von Willebrand disease is caused by a deficiency in which factor?

Answer 4

Von Willebrand factor deficiency

Question 5

What inheritance pattern is shown in Haemophilia A/B?

Answer 5

X-linked recessive inheritance

• affected men’s sons normal
• daughter of affected individual = carrier (inherits mutated X chromosome from father)

Question 6

Impact of haemophilia

Answer 6

bruising
retinal bleed
repeated bleeds into joints + severe arthritis

Question 7

What is the inheritance pattern of Von Willebrand disease?

Answer 7

Autosomal (dominant or recessive)
- depend on exact mutation and their functional impact

Question 8

Von Willebrand factor function

Answer 8

carrier molecule for circulating factor 8
promotes adhesion of the platelets to a damaged endothelium

Question 9

What mutation causes severe Haemophilia A?

Answer 9

flip tip inversion
complete absence of coagulation factor