Molecular and Clinical Biology of von Willebrand Disease Study

This research study will compare bleeding symptoms (or lack of bleeding symptoms) to each of the following:

1. Routine laboratory tests used to diagnosed von Willebrand disease (VWD).
2. New genetic or specialized tests of how von Willebrand Factor (VWF) works.
3. Determine if other genes or proteins might cause you to have (or not have) bleeding symptoms or abnormal VWD laboratory tests results.

The study will also verify if patients have VWD.

In order to participate you must meet the following criteria:

• Have VWD.
• Are at least 2 years of age.

This is a partial list of eligibility requirements.