Bernard-Soulier Syndrome
Description
Bernard-Soulier Syndrome (BSS) is a rare inherited bleeding disorder affecting the blood‘s ability to clot. It‘s characterized by abnormally large platelets, called giant platelets, that have trouble sticking together (aggregating) to form a clot. This can lead to prolonged bleeding, even after minor injuries.
Genes Involved
Bernard-Soulier Syndrome is caused by mutations in genes involved in the production of certain proteins that are essential for platelet function, specifically:
- GPIBα (also known as ITGA2B): This gene provides instructions for making one part of the glycoprotein Ib-IX-V complex, a receptor found on the surface of platelets. It plays a crucial role in platelet adhesion to von Willebrand factor (vWF), a protein that helps platelets stick to damaged blood vessels.
- GPIX (also known as ITGB3): This gene provides instructions for making another part of the glycoprotein Ib-IX-V complex.
- GPV (also known as ITGA2A): This gene provides instructions for making part of the glycoprotein Ib-IX-V complex.
Recognizing the Signs and Symptoms
The most common symptom of Bernard-Soulier Syndrome is easy bruising and prolonged bleeding, even from minor cuts or scrapes. Other signs and symptoms can include:
- Bleeding from the nose (epistaxis)
- Heavy menstrual bleeding in females
- Bleeding in the gastrointestinal tract
- Bleeding in the brain (intracranial hemorrhage)
- Delayed wound healing
- Easy bruising
- Purpura (small, flat, reddish-purple spots on the skin)
The severity of bleeding episodes varies among individuals with Bernard-Soulier Syndrome.
Causes
Bernard-Soulier Syndrome is caused by mutations in genes involved in platelet function. These mutations are inherited from a parent, meaning the disorder is passed down through families. Most cases are caused by mutations in the GPIBα gene.
Inheritance/recurrence risk
Bernard-Soulier Syndrome is inherited in an autosomal recessive pattern, which means that both parents must carry the gene mutation for a child to inherit the disorder. If both parents carry the gene mutation, there is a 25% chance that each child will inherit the disorder. If one parent carries the gene mutation, there is a 50% chance that each child will be a carrier of the gene mutation, but not have the disorder.
