Novel mutation in the glycoprotein Ibβ in a patient with Bernard-Soulier syndrome: possibility of distant parental consanguinity.

Bernard-Soulier syndrome (BSS) is a rare autosomal recessive disorder characterized by a prolonged skin-bleeding time and thrombocytopenia with giant platelets. The hallmark of BSS is an abnormal platelet attachment to the vessel wall due to reduced or abnormal glycoprotein Ib/IX/V complex. We present a case of BSS in a 14-month-old boy caused by a novel genetic mutation. The patient has the typical clinical findings of BSS, but he was misdiagnosed for a long period. Evaluation of the peripheral blood smear revealed giant platelets and genetic testing confirmed the diagnosis of BSS. The child was found to be homozygous for a nonsense mutation (c.423C > A) in the glycoprotein Ibβ (GPIbβ) gene. Knowing that we are dealing with a very rare syndrome, the detected mutation in our patient was homozygous. Although the parents were nonconsanguineous, we believe that they were related in a distant parental connection, which the parents and their family were not aware of.