Primary Sj?gren's syndrome (SS) shares many features with systemic lupus erythematosus (SLE). Here we investigated the association of the three major polymorphisms in IRF5 and STAT4 found to be associated with SLE, in patients from Sweden and Norway with primary SS. These polymorphisms are a 5-bp CGGGG indel in the promoter of IRF5, the single nucleotide polymorphism (SNP) rs10488631 downstream of IRF5 and the STAT4 SNP rs7582694, which tags the major risk haplotype of STAT4. We observed strong signals for association between all three polymorphisms and primary SS, with odds ratios (ORs) >1.4 and P-values
The objective of this study was to investigate the possible association between mitochondrial DNA polymorphisms and systemic lupus erythematosus (SLE). A cohort from the Department of Rheumatology, Lund University Hospital, Sweden, consisting of 166 unrelated SLE patients was investigated as well as 190 unrelated healthy blood donors. Mean age at SLE diagnosis was 39 years (range 10-83) and mean follow-up time was 16 years (range 1-44). There were 87% women among the lupus patients, and the control group consisted of 98 women and 92 men from the same geographical area and with a similar age and ethnicity. The mtDNA SNP nt16189C was associated with SLE (OR = 1.98, 95% CI 1.04-3.78, P = 0.05). In addition, SNP nt13708A was associated with SLE in males (OR = 3.46, 95% CI 1.08-11.1, P = 0.04), although the number of male patients was low. Furthermore, SNP nt10398A was associated with secondary anti-phospholipid syndrome (P = 0.017, OR 8.2, 95% CI 1.1-63). In conclusion, in this study, we have for the first time investigated the possible association between SLE disease and mitochondrial DNA polymorphisms. Altogether, these novel results suggest that mtDNA polymorphisms may be associated with development of SLE and may potentially be of importance in SLE pathogenesis.
Single-nucleotide polymorphisms (SNPs) in the major histocompatibility complex class II transactivator (MHC2TA) gene encoding the class II transactivator have been associated with multiple sclerosis, rheumatoid arthritis, and myocardial infarction in the Swedish population. We used a case-control approach to investigate the prevalence of a relevant variant in Swedish systemic lupus erythematosus (SLE) cohorts to determine whether SLE shares the same MHC2TA susceptibility allele as the other diseases. No differences were observed between cases and control subjects at either the allele or genotype levels. Furthermore, no significant correlations were found when comparing different clinical and serological SLE phenotypes. This particular polymorphism rs3087456 of the MHC2TA gene does not appear to influence genetic susceptibility to SLE in the Swedish population. We conclude that our data support neither allelic nor genotype association between the MHC2TA SNP and SLE.