Similarly, the prevalence of the BAFF-var allele among healthy control subjects from another northern country (the Netherlands) was 3.8%, and the MAF was 1.91%. study was approved by the local ethics committees of the participating centers (University Hospital Geneva, 06C100; University Hospital Lausanne, 04/07; University Dexrazoxane HCl Hospital Bern, KEK-BE 045/07; University Hospital Basel, EKBB 262/06; University Hospital Essen, 12C5149-BO). All patients signed a written informed consent. Genotyping Genomic DNA was isolated from 153 whole-blood samples from SSCS using the QIAamp DNA Blood Midi Kit (QIAGEN GmbH, Hilden, Germany) according to the manufacturers instructions. For the 42 SLE patients from the University Hospital Essen, DNA was purified from peripheral blood leukocytes as previously described [22]. For polymerase chain reaction (PCR), 50?ng of genomic DNA was amplified in a reaction tube containing 5?pmol of each primer (BAFFVRF, 5-CTCAGAAGACAGCATCCCGGT-3; BAFFVRR, 5-GAGAAGAATGCTTGGCCTGCT-3), 1x reaction buffer, 1?U DNA Taq DNA Polymerase (QIAGEN GmbH, Hilden, Germany) and 200?M of deoxyribonucleotide triphosphate (dNTP Mix; Promega GmbH, Mannheim, Germany). Cycling parameters were as follows: initial denaturation at 94?C for 2?min, 35?cycles at 94?C for 15?s, annealing at 60?C for 30?s, at 72?C for 1?min, and a final extension step at 72?C for 7?min. PCR products were analyzed by electrophoresis in a 1.5% agarose gel stained with ethidium bromide for identifying the BAFF-specific products (890?bp) for use as a template in sequencing reactions. PCR samples were purified with the QIAquick 96 PCR Purification Kit (QIAGEN GmbH, Hilden, Germany). Sequencing reactions were performed with the BAFFVRS C5-TCAGATATGGAACATACTCACAT-3 primer and the BigDye Terminator? v1.1?Cycle Sequencing Kit (Thermo Fisher Scientific, Schwerte, Germany), essentially as described by the manufacturer. Sequencing products were run on an ABI 3130XL Genetic Analyzer (Applied Biosystems, Foster City, CA, USA). Data analysis Dexrazoxane HCl was performed with Chromas software version 2.6.5 (Technelysium, South Mouse monoclonal to MAPK11 Brisbane, Australia). Statistical analysis Data are given as absolute numbers and percentages or as means standard deviation. Dexrazoxane HCl For comparisons of two groups one-tailed Chi-square tests were carried out. The level of statistical significance was set at confidence interval; central nervous system; odds ratio Table 3 Association of the BAFF-var allele with routine serological parameters and disease activity of systemic lupus erythematosus among 195 patients Open in a separate window antinuclear antibodies; confidence interval; double stranded DNA; odds ratio; physicians global assessment; Systemic Lupus Erythematosus Disease Activity Index Taking into account disease activity of SLE at the time of inclusion, patients with the BAFF-var allele exhibited severe disease as assessed by the attending physician (and subsequently defined as PGA??2) more frequently (7 of Dexrazoxane HCl 14, 50%) than did those without this allele (24 of 139, 17%) (confidence interval; odds ratio Discussion This study found that the prevalence of the TNFSF13B BAFF-var among German and Swiss SLE patients was 9.2%. Patients with the BAFF-var genotype were more likely to exhibit signs of renal involvement, such as lupus nephritis, proteinuria, and hematuria. Compared to SLE patients who do not carry the BAFF-var allele, those carrying the allele displayed increased disease activity at the Dexrazoxane HCl time of study entry and more frequently required intensive treatment with immunosuppressive agents. Previous studies demonstrated that the frequency of the BAFF-var allele was higher among SLE patients from various European cohorts than among the corresponding control populations, a finding suggesting a relationship between the BAFF-var and SLE [17, 19]. The frequency of BAFF-var allele carriers (9.2%) and the MAF of the BAFF-var allele (4.6%) identified in our SLE study cohort were in line with and support the findings of case-control studies performed by Gonzlez-Serna et al. [19]. We detected the BAFF-var allele in 7.1% of SLE patients in our German cohort and the corresponding MAF was 3.69%. In comparison, the frequency of the BAFF-var allele (4%) and the MAF (2.02%) among the healthy German population were markedly lower. Similarly, the prevalence of the BAFF-var allele among healthy control subjects from another northern country (the Netherlands) was 3.8%, and the MAF was 1.91%. Among healthy subjects from Spain, the frequency (8.8%) and MAF (4.2%) of the BAFF-var allele were increased; however, among the corresponding Spanish SLE cohort the prevalence and MAF of the BAFF-var allele were even higher than in healthy control subjects with 10.8 and 5.81%, respectively [19]. These variations are mainly due to the previously described north-south gradient.