Beta 2 glycoprotein I Valine247Leucine polymorphism in patients with antiphospholipid syndrome

Abstract

Aim: Beta 2 Glycoprotein I (β2-GP I) takes part in the pathogenesis of antiphospholipid syndrome (APS). Valine247Leucine (Val247Leu) gene polymorphism of β2-GP I might affect the binding/production of anti-β2-GP I antibodies. Multiple studies are showing different frequencies of this polymorphism in various ethnic backgrounds; we aimed to determine the frequency and clinical importance of Val247Leu gene polymorphism of β2-GP I in patients with APS and healthy.

Methods: Eighty-three patients with APS [68 primary APS, 15 APS with systemic lupus erythematosus (SLE)] and 63 healthy individuals were included. Β2-GP I Val247Leu polymorphism was determined by quantitative real time polymerase chain reaction and melting curve analysis. The presence of anti-β2-GP I antibodies was detected by ELISA in the patient group.

Results: Allele and genotype frequencies were similar between patients and healthy controls (p=0,307). V allele and VV genotype frequencies were significantly higher in primary APS patients with thrombocytopenia (p=0.040). There was no significant difference between β2-GP I Val247Leu gene polymorphism and the anti-β2-GP IgM and IgG antibody levels in the patient group (p=0.631 and p=0.077, respectively)

Conclusion: This is the first study investigating the β2-GP I Val247Leu gene polymorphism in the Turkish population. The frequencies of Val247Leu gene polymorphism of β2-GP I were not different between patients with APS and healthy individuals in line with the other studies in Caucasian populations. Significantly high levels of V allele and VV genotype frequencies in primary APS patients could offer further insight to into the pathogenesis of thrombocytopenia in APS.