To determine the impact of a broad spectrum of different polymorphisms within the interleukin-10 (IL-10) promoter gene on disease susceptibility to primary Sjogren's syndrome (pSS), clinical manifestations, and autoantibody production.
We genotyped 111 unrelated German Caucasian patients with pSS and 145 healthy controls for the single nucleotide polymorphisms (SNPs) at positions -2849, -2776, -2769, -2763, -1349, -1082, -851, -819, -657, and -592 and for the microsatellites IL10.R and IL10.G. Allele and haplotype distributions were compared between patients and controls and between subgroups of patients with different clinical and laboratory findings.
We found no significant differences in the allele or haplotype frequencies between pSS patients and healthy controls. After Bonferroni correction we found a significant association of the ACC haplotype (at the -1082, -819, and -592 loci) with immunoglobulin (Ig)A antibodies to anti-alpha-fodrin.
Overall we found no associations of IL-10 promoter polymorphisms with the susceptibility to pSS in our cohort. The finding that the production of IgA anti-alpha-fodrin antibodies is associated with polymorphisms within the IL-10 promoter region suggests a genetic contribution to the generation of these antibodies.