FYB gene polymorphisms are associated with susceptibility for systemic lupus erythemathosus (SLE)

Systemic Lupus Erythematosus (SLE) is a multifactorial autoimmune disease affecting different organs or systems. Several genes have been associated with SLE susceptibility so far. A previous study has reported, in SLE patients, a differential expression of Fyn Binding Protein gene (FYB), encoding for a protein participating in the T cells signaling cascade and in the interleukin-2A expression modulation. This study investigates the association of 10 FYB SNPs with differential susceptibility to SLE in 143 SLE patients and 184 controls from Southern Brazil. Significant differences were observed when comparing allele and genotype frequencies distribution in patients and controls: the T allele for rs6863066 C>T SNP and C for rs358501 T>C SNP were significantly more frequent in SLE patients than in controls (p=0.0002 and p=0.008) and associated with an increased risk for SLE (OR=1.93 and OR=1.69). The frequencies of rs6863066 C/T and T/T and rs358501 C/C genotypes were significantly higher in patients than in controls (p=0.001, p=0.006 and p=0.008). A significant association was also found for the rs6863066-rs358501 T-T and T-C haplotypes (OR=2.06, p=0.002 and OR=2.93, p=0.001). When considering clinical and laboratorial manifestations, an association was found between rs2161612 G allele and G/G genotype and hematological alterations (p=0.008) and rs379707 A/C genotype and anti-dsDNA (p=0.01). In conclusion, our findings indicate an association between polymorphisms located in FYB gene and SLE, suggesting their possible involvement in disease susceptibility and clinical manifestations.