The association between P selectin glycoprotein ligand 1 gene variable number of tandem repeats polymorphism and risk of thrombosis in Behçet's disease.

Objectives: Behçet's disease (BD) has been recognized as an unclassified type of vasculitis with an accompanying tendency to thrombosis. No disease-specific pathology has been demonstrated so far to explain the prothrombotic state, and this predisposition is considered to be associated with endothelial activation/dysfunction. P-selectin glycoprotein ligand-1 (PSGL-1) variable number of tandem repeat (VNTR) polymorphism has an impact on the protein length, and heterozygosity affect of the PSGL-1 to P-selectin interaction, which has been found to be associated with an increased risk of thrombosis in patients with antiphospholipid syndrome. We aimed to analyze the association of PSGL-1 gene polymorphism, in a group of BD patients with and without thrombosis.

Methods: The study group consisted of 136 BD patients (112 male, 24 female) with thrombosis, 120 BD patients without thrombosis (54 male, 66 female) during at least 5 years disease course, and 190 healthy controls (103 male, 87 female) All patients fulfilled the International Study Group criteria for classification of BD. Genotyping for the PSGL-1 gene exon 2 VNTR polymorphism was carried out with the amplification of genomic DNA and running of the polymerase chain reaction product on agarose gel electrophoresis.

Results: The frequency of heterozygous genotypes (AB+AC+BC) was greater in BD patients with thrombosis compared to BD patients without thrombosis (33.1% vs. 20.8%, P = 0.028, odds ratio = 1.85). However, the increased frequency of heterozygous genotypes in BD patients with thrombosis did not reach a statistically significant level compared to healthy controls (33.1% vs. 32.6%).

Conclusions: PSGL-1 VNTR polymorphism may have limited contribution to the thrombotic tendency in patients with BD.