Thrombocytopenia in patients with 22q11.2 deletion syndrome and its association with glycoprotein Ib-β

Abstract

Purpose: To elucidate whether thrombocytopenia in 22q11.2 deletion syndrome patients is associated with the hemizygosity of glycoprotein Ib-β and to clarify the correlation of phenotype and genotype of this gene in 22q11.2 deletion syndrome patients with thrombocytopenia.Methods: Platelet number, mean platelet volume, platelet agglutination, and the protein level of glycoprotein Ib-β were measured in 22q11.2 deletion syndrome patients and controls. Phenotypes other than that of thrombocytopenia were also analyzed in these patients.Results: The 22q11.2 deletion syndrome patients with thrombocytopenia had a larger mean platelet volume, lower agglutination to ristocetin, and lower protein level of glycoprotein Ib-β than control patients. The 22q11.2 deletion syndrome patients with thrombocytopenia showed an increased risk of developing schizophrenia.Conclusions: Thrombocytopenia in 22q11.2 deletion syndrome patients is associated with decreased expression of glycoprotein Ib-β because of the hemizygosity. 22q11.2 deletion syndrome patients with thrombocytopenia require total management, especially for schizophrenia.