TNFSF13B and synovial sarcoma: While the allele analysis for the prevalence of the five studied BAFF SNPs between the primary SS groups with or without fatigue revealed no statistically significant differences (Supplementary Table 4), the TT genotype of the rs9514828 BAFF SNP was less frequent in fatigued compared to non-fatigued primary SS patients (14.1% vs 33.3%, OR [95%CI]: 0.33 [0.15-0.72], p=0.003 and 0.42 [0.23-0.78], p=0.005 in the dominant and overdominant models respectively) (Table 1).