The complement binding protein gene cluster containing C4BPB and C4BPA mapped as new genetic risk factor for venous thrombosis (VT) by means of genome-wide association mapping studies (GWAS) in the GAIT cohort (1), a VT-risk group (2), targeted SNP typing in the GHS study (3), single SNP case-control analyses (rs3813948) of the MARTHA and FARIVE cohorts (4). Key linkage disequilibrium (LD) relationships between key SNPs employed by Buil et al in the context of studies. Significant support and key nonsignificance of assays are shown as red and blue, respectively. Significance was observed only for a combined analysis of both cohorts, but not for each cohort separately. FPS, free plasma protein S; PS, total plasma protein S, PROS1, protein S gene.