Bernard-Soulier syndrome is a bleeding disorder associated with abnormal platelets, which are blood cells involved in blood clotting. In affected individuals, platelets are unusually large and fewer in number than usual (a combination known as macrothrombocytopenia). People with Bernard-Soulier syndrome tend to bruise easily and have an increased risk of nosebleeds (epistaxis). They may also experience abnormally heavy or prolonged bleeding following minor injury or surgery or even without trauma (spontaneous bleeding). Rarely, bleeding under the skin causes tiny red or purple spots on the skin called petechiae. Women with Bernard-Soulier syndrome often have heavy or prolonged menstrual bleeding (menorrhagia).
Bernard-Soulier syndrome is caused by mutations in one of three genes: GP1BA, GP1BB, or GP9. The proteins produced from these genes are pieces (subunits) of a protein complex called glycoprotein (GP)Ib-IX-V. This complex is found on the surface of platelets and plays an important role in blood clotting.
Bernard-Soulier syndrome is estimated to occur in 1 in 1 million individuals; however, some doctors think the condition is underdiagnosed and may be more common.
Most cases of Bernard-Soulier syndrome are inherited in an autosomal recessive pattern, which means both copies of the GP1BA, GP1BB, or GP9 gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene. Although most people with only one copy of the mutated gene do not show signs and symptoms of the condition, some have platelets that are slightly larger than normal or very mild bleeding abnormalities.
Published Date: January 01, 2020Published By: National Institutes of Health