Table 2.
Some molecular and physiological characteristics of hemophilia A and B
| Type of hemophilia | Deficient factor | Protein size (Kilodaltons) | DNA length (bp) | Half life (Hours) | Function in the coagulation cascade | Plasma concentration (ng/ml)1,2 | ||
|---|---|---|---|---|---|---|---|---|
| |
|
|
|
|
|
Mild hemophilia |
Moderately Severe Hemophilia |
Severe Hemophilia |
| Hemophilia A |
VIII |
280 |
7056 |
8-12 |
Activated by thrombin and activates to FX3 |
10-80 (5-40%) |
2-10 (1-5%) |
< 2 (<1%) |
| Hemophilia B | IX | 68 | 1389 | 15-25 | Activated by FXIa4, and activates to FX | 500-2000 (5-40%) | 50-500 (1-5%) | < 50 (<1%) |
1Normal plasma level of coagulation factors: Factor VIII, 200 ng/mL; factor IX, 5000 ng/mL; 2One International Unit (IU) of factor VIII or IX, per kg of body weight, increases the activity of factor in plasma, 1% to 2% of normal level; 3FX, factor X; 4FXIa, factor XI activated.