We performed a genome-wide association study (GWAS) of systemic lupus erythematosus (SLE) in a Chinese Han population by genotyping 1,047 cases and 1,205 controls using Illumina Human610-Quad BeadChips and replicating 78 SNPs in two additional cohorts (3,152 cases and 7,050 controls). We identified nine new susceptibility loci (ETS1, IKZF1, RASGRP3, SLC15A4, TNIP1, 7q11.23, 10q11.22, 11q23.3 and 16p11.2; 1.77 x 10(-25) < or = P(combined) < or = 2.77 x 10(-8)) and confirmed seven previously reported loci (BLK, IRF5, STAT4, TNFAIP3, TNFSF4, 6q21 and 22q11.21; 5.17 x 10(-42) < or = P(combined) < or = 5.18 x 10(-12)). Comparison with previous GWAS findings highlighted the genetic heterogeneity of SLE susceptibility between Chinese Han and European populations. This study not only advances our understanding of the genetic basis of SLE but also highlights the value of performing GWAS in diverse ancestral populations.

SummaryTo study the clinical and epidemiological profile of Pityriasis versicolor (PV) and to determine the possible genetic model for PV in Chinese Han, we investigated 503 patients with PV who were recruited by a questionnaire method. Statistical analysis, heritability and complex segregation analysis were performed using EPI INFO 6.0, SPSS 10.0, the Falconer method and the SAGE-REGTL programs. In the total 503 PV patients, the mean age of onset was 22.85 ± 10.36 years. For male and female patients, the peak ages of initial onset were both 20-29 years. A total of 106 (21.1%) patients were reported to have a positive family history of PV. The mean age of onset in males with positive family history was earlier than those with negative family history (t = 3.58, P < 0.01). Higher rate of recurrence and longer duration were seen in the patients with positive family history than those with negative family history. The heritability of PV in first-, second-and third-degree relatives was 48.13%, 40.11% and 27.20% respectively. Based on the REGTL results, the best model was a polygenic additive model for PV.

Our results might be helpful for explaining the missing heritability of the psoriasis due to epistasis and provide a deep insight into the important role of the IL23/Th17 pathway in the pathogenesis of psoriasis.

BackgroundPityriasis rosea is a common papulosquamous disorder. However, its etiology and pathogenesis remain unclear.ObjectiveWe investigate the types of inflammatory cells infiltrating the lesional skin of pityriasis rosea and demonstrate whether T-cell-mediated immunity is involved in the pathogenesis of this condition or not.MethodsThe biopsies were taken from the lesional skin of 35 cases of patients diagnosed with pityriasis rosea. The specimens were prepared in paraffin sections, then submitted to routine immunohistochemistry procedures using monoclonal antibodies directed against CD3, CD4, CD8, CD20 and CD45RO and horseradish peroxidase-labeled goat anti-human antibodies. The positive sections were determined by the ratio and staining intensity of positive inflammatory cells.ResultsThe mean score of positive CD3, CD4, CD8, and CD45RO staining was respectively 3.74±3.88, 5.67±4.40, 2.94±3.42 and 7.68±4.33 in these pityriasis rosea patients (P<0.001). The percentage of positive staining was 54.29% (19/35), 69.7% (23/33), 40% (14/35) and 79.41% (27/34) (P<0.05). However, the staining of CD20 was negative in all samples. The mean score of CD3 staining in patients with time for remission ≤60 days (4.90±4.21) was higher than that in patients with time for remission >60 days (2.00±2.5) (P<0.05), whereas no statistical difference in the mean score of CD4, CD8 and CD45RO staining was observed. study liMitations: The sample size and the selected monoclonal antibody are limited, so the results reflect only part of the cellular immunity in the pathogenesis of pityriasis rosea.ConclusionOur findings support a predominantly T-cell mediated immunity in the development of pityriasis rosea.