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Vitiligo is an immune-related disease with patchy depigmentation of skin and hair caused by selective destruction of melanocytes. In recent decades, many studies have shown the association between vitiligo and HLA genes; however, the results of Han Chinese are scarce. In this study, we performed a fine-mapping analysis of the MHC region in 2818 Han Chinese subjects through a widely used HLA imputation method with a newly built large-scale Han-MHC reference panel. Three new four-digit HLA alleles (HLA-DQB1 ∗ 02:02, HLA-DQA1 ∗ 02:01 and HLA-DPB1 ∗ 17:01) were identified to be associated with the risk of vitiligo, and four previously reported alleles were confirmed. Further conditional analysis revealed that two important variants, HLA-DQβ1 amino acid position 135 (OR = 1.79, P = 1.87 × 10 -11 ) and HLA-B amino acid positions 45-46 (OR = 1.44, P = 5.61 × 10 -11 ), conferred most of the MHC associations. Three-dimension ribbon models showed that the former is located within the β2 domain of the HLA-DQβ1 molecule, and the latter lies in the α1 domain of the HLA-B molecule, while both are involved in specific antigen presenting process. Finally, we summarized all significant signals in the MHC region to clarify their complex relationships, and 8.60% of phenotypic variance could be explained based on all reported variants in Han Chinese so far. Our findings highlight the complex genetic architecture of the MHC region for vitiligo in Han Chinese population and expand our understanding of the roles of HLA coding variants in the etiology of vitiligo., (Copyright © 2018. Published by Elsevier B.V.)

Background: Vitiligo is an autoimmune disease, characterized by progressive loss of skin pigmentation, which is caused by the interactions of multiple factors, such as heredity, immunity and environment. Recently, a single nucleotide polymorphism (SNP) rs638893 at 11q23.3 region was identified as a risk factor for vitiligo in genome-wide association studies and multiple SNPs in this region have been associated with other autoimmune diseases., Objective: This study aims to identify additional susceptibility variants associated with vitiligo at 11q23.3 in the Chinese Han population., Methods: We selected and genotyped 26 SNPs at 11q23.3 in an independent cohort including 2924 cases and 4048 controls using the Sequenom MassArray iPLEX ® system. Bonferroni adjustment was used for multiple comparisons and P value <1.92×10 -3 (0.05/26) was considered statistically significant., Results: The A allele of rs613791 and G allele of rs523604 located in CXCR5 were observed to be significantly associated with vitiligo (OR=1.21, 95% CI: 1.11-1.31, P=1.20×10 -5 ; OR=1.14, 95% CI: 1.07-1.23, P=1.90×10 -4 , respectively). The C allele of rs638893 (a previously reported one) located upstream of DDX6 was also significantly associated with vitiligo (OR=1.25, 95% CI: 1.12-1.38, P=3.04×10 -5 ). The genotypes distribution of 3 SNPs also showed significant differences between case and control (rs613791: P=7.00×10 -6 , rs523604: P=4.00×10 -3 , rs638893: P=1.20×10 -5 , respectively). The two newly identified SNPs (rs613791 and rs523604) showed independent associations with vitiligo by linkage disequilibrium analysis and conditional logistic regression., Conclusions: The study identified two new independent signals in the associated locus 11q23.3 for vitiligo. The presence of multiple independent variants emphasizes an important role of this region in disease susceptibility., (Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.)

In a previous large-scale exome sequencing analysis for psoriasis, we discovered seven common and low-frequency missense variants within six genes with genome-wide significance. Here we describe an in-depth analysis of noncoding variants based on sequencing data (10,727 cases and 10,582 controls) with replication in an independent cohort of Han Chinese individuals consisting of 4,480 cases and 6,521 controls to identify additional psoriasis susceptibility loci. We confirmed four known psoriasis susceptibility loci (IL12B, IFIH1, ERAP1 and RNF114; 2.30 × 10(-20)≤P≤2.41 × 10(-7)) and identified three new susceptibility loci: 4q24 (NFKB1) at rs1020760 (P=2.19 × 10(-8)), 12p13.3 (CD27-LAG3) at rs758739 (P=4.08 × 10(-8)) and 17q12 (IKZF3) at rs10852936 (P=1.96 × 10(-8)). Two suggestive loci, 3p21.31 and 17q25, are also identified with P<1.00 × 10(-6). The results of this study increase the number of confirmed psoriasis risk loci and provide novel insight into the pathogenesis of psoriasis.

To explore the contribution of functional coding variants to psoriasis, we analyzed nonsynonymous single-nucleotide variants (SNVs) across the genome by exome sequencing in 781 psoriasis cases and 676 controls and through follow-up validation in 1,326 candidate genes by targeted sequencing in 9,946 psoriasis cases and 9,906 controls from the Chinese population. We discovered two independent missense SNVs in IL23R and GJB2 of low frequency and five common missense SNVs in LCE3D, ERAP1, CARD14 and ZNF816A associated with psoriasis at genome-wide significance. Rare missense SNVs in FUT2 and TARBP1 were also observed with suggestive evidence of association. Single-variant and gene-based association analyses of nonsynonymous SNVs did not identify newly associated genes for psoriasis in the regions subjected to targeted resequencing. This suggests that coding variants in the 1,326 targeted genes contribute only a limited fraction of the overall genetic risk for psoriasis.

Background: Androgenetic alopecia (AGA) is a well-characterized type of progressive hair loss commonly seen in men, with different prevalences in different ethnic populations. It is generally considered to be a polygenic heritable trait. Several susceptibility genes/loci, such as AR/EDA2R, HDAC9 and 20p11, have been identified as being involved in its development in European populations. In this study, we aim to validate whether these loci are also associated with AGA in the Chinese Han population., Methods: We genotyped 16 previously reported single nucleotide polymorphisms (SNPs) with 445 AGA cases and 546 healthy controls using the Sequenom iPlex platform. The trend test was used to evaluate the association between these loci and AGA in the Chinese Han population. Conservatively accounting for multiple testing by the Bonferroni correction, the threshold for statistical significance was P ≤ 3.13 × 10(-3)., Results: We identified that 5 SNPs at 20p11 were significantly associated with AGA in the Chinese Han population (1.84 × 10(-11) ≤ P ≤ 2.10 × 10(-6))., Conclusions: This study validated, for the first time, that 20p11 also confers risk for AGA in the Chinese Han population and implicated the potential common genetic factors for AGA shared by both Chinese and European populations.

Systemic lupus erythematosus (SLE) is a prototype autoimmune disease with a strong genetic involvement and ethnic differences. Susceptibility genes identified so far only explain a small portion of the genetic heritability of SLE, suggesting that many more loci are yet to be uncovered for this disease. In this study, we performed a meta-analysis of genome-wide association studies on SLE in Chinese Han populations and followed up the findings by replication in four additional Asian cohorts with a total of 5,365 cases and 10,054 corresponding controls. We identified genetic variants in or near CDKN1B, TET3, CD80, DRAM1, and ARID5B as associated with the disease. These findings point to potential roles of cell-cycle regulation, autophagy, and DNA demethylation in SLE pathogenesis. For the region involving TET3 and that involving CDKN1B, multiple independent SNPs were identified, highlighting a phenomenon that might partially explain the missing heritability of complex diseases., (Copyright © 2013 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)