The effect of circulating cytokines on the risk of systemic lupus erythematosus: Mendelian randomization and observational study.

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder, the etiology of which involves the alterations in circulating cytokine levels. However, the cause-and-effect relationships and in-depth clinical relevance of them remain to be systematically investigated. We conducted a two-sample Mendelian randomization (MR) study to assess the causality of circulating cytokine levels and SLE and found that genetically determined elevated CTACK and IL-18 were associated with an increased risk of SLE, whereas a higher level of GRO-a was associated with decreased risk. Furthermore, we performed an observational study to further reveal the association between 27 cytokines and the severity measured by SLEDAI score, as well as lupus nephritis (LN), of SLE. We identified six cytokines (MCP1, MIP1ß, CTACK, IP10, HGF, IL18, IL13) that were identified as associated with the clinical severity of SLE, and five cytokines, especially IL18, were related with LN and may have good diagnostic value. Moreover, we also predicted four compounds that might have good binding activities with IL18. The evidence supported a potential causal role of circulating cytokines on the risk of SLE. Targeting IL18 might be a meaningful strategy for the prevention or treatment of SLE, especially in LN patients.

Systemic Analysis of the Prognosis-Related RNA Alternative Splicing Signals in Melanoma.

BACKGROUND Alternative splicing (AS), the mechanism underlying the occurrence of protein diversity, may result in cancer genesis and development when it becomes out of control, as suggested by a growing number of studies. However, systemically analyze of AS events at the genome-wide level for skin cutaneous melanoma (SKCM) is still in a preliminary phase. This study aimed to systemically analyze the bioinformatics of the AS events at a genome-wide level using The Cancer Genome Atlas (TCGA) SKCM data. MATERIAL AND METHODS The SpliceSeq tool was used to analyze the AS profiles for SKCM clinical specimens from the TCGA database. The association between AS events and overall survival was analyzed by Cox regression analysis. AS event intersections and a gene interaction network were established by UpSet plot. A multivariate survival model was used to establish a feature genes prognosis model. RESULTS A total of 103 SKCM patients with full clinical parameters available were included in this study. We established an AS network that investigated the relationship between AS events and clinical prognosis information. Furthermore, 4 underlying feature genes of SKCM (MCF2L, HARS, TFR2, and RALGPS1) were found in the AS network. We performed function analysis as well as correlation analysis of AS events with gene expression. Using the multivariate survival model, we further confirmed the 4 genes that impacted the classifying SKCM prognosis at the level of AS events as well as gene expression, especially in wild-type SKCM. CONCLUSIONS AS events could be ideal indicators for SKCM prognosis. The key feature gene MCF2L played an important role in wild-type SKCM.

The genetic basis of pigmentation in alopecia areata.

Alopecia areata (AA) is a common hair loss disorder characterized by discrete, well demarcated areas of non-scarring terminal hair alopecia, with the calculated lifetime risk of ~2%. In past decades, linkage and GWA studies have implicated dozens of susceptibility genes/loci that are linked to the development of AA. Fischer et al performed a genome-wide CNV analysis of 585 AA patients and 1,340 controls in a European population. This is the first genome-wide study of CNV to be performed in AA samples, and the association finding in the MCHR2 gene region further underscores the potential role of pigmentation in AA development.

Genome-wide copy number variation study in anorectal malformations.

Anorectal malformations (ARMs, congenital obstruction of the anal opening) are among the most common birth defects requiring surgical treatment (2-5/10 000 live-births) and carry significant chronic morbidity. ARMs present either as isolated or as part of the phenotypic spectrum of some chromosomal abnormalities or monogenic syndromes. The etiology is unknown. To assess the genetic contribution to ARMs, we investigated single-nucleotide polymorphisms and copy number variations (CNVs) at genome-wide scale. A total of 363 Han Chinese sporadic ARM patients and 4006 Han Chinese controls were included. Overall, we detected a 1.3-fold significant excess of rare CNVs in patients. Stratification of patients by presence/absence of other congenital anomalies showed that while syndromic ARM patients carried significantly longer rare duplications than controls (P = 0.049), non-syndromic patients were enriched with both rare deletions and duplications when compared with controls (P = 0.00031). Twelve chromosomal aberrations and 114 rare CNVs were observed in patients but not in 868 controls nor 11 943 healthy individuals from the Database of Genomic Variants. Importantly, these aberrations were observed in isolated ARM patients. Gene-based analysis revealed 79 genes interfered by CNVs in patients only. In particular, we identified a de novo DKK4 duplication. DKK4 is a member of the WNT signaling pathway which is involved in the development of the anorectal region. In mice, Wnt disruption results in ARMs. Our data suggest a role for rare CNVs not only in syndromic but also in isolated ARM patients and provide a list of plausible candidate genes for the disorder.

Next-generation sequencing detection and characterization of a heterozygous novel splice junction mutation in the 2B domain of KRT1 in a family with diffuse palmoplantar keratoderma.

Diffuse palmoplantar keratoderma (DPPK) is an autosomal-dominant genodermatosis characterized by restricted, uniform hyperkeratosis on the palm and sole epidermis. DPPK is normally associated with dominant-negative mutations in the keratin-encoding gene, KRT1. We report a heterozygous novel point mutation in the exon 6 splice donor site of KRT1 (c.1254G>C) by next-generation sequencing, resulting in the formation of two alternative transcripts, which segregates with DPPK in a four-generation Chinese family. This results in both the complete loss of exon 6 and the simultaneous utilization of a novel in-frame splice site 54 bases downstream of the mutation with the subsequent deletion of 42 amino acids and the insertion of 18 amino acids into the protein's 2B domain. This is the first report of a novel splice donor site mutation with aberrant splicing and the formation of two alternative transcripts causing DPPK. This study also demonstrates the value of next-generation sequencing in the identification of novel disease-causing mutations.

A comprehensive association analysis confirms ZMIZ1 to be a susceptibility gene for vitiligo in Chinese population.

BACKGROUND: ZMIZ1 has been shown to be associated with multiple autoimmune diseases and play a role in the development of melanocyte. The association of ZMIZ1 with vitiligo was also suggested, but the evidence did not reach genome-wide significance and has not been confirmed by independent studies. METHODS: A fine mapping analysis of the ZMIZ1 locus was carried out in the dataset of 1117 vitiligo patients and 3437 controls through deep imputation. Ten suggestive SNPs were then analysed in an independent validation cohort of 7458 cases and 7542 controls. SNPs within ZMIZ1 locus were functionally annotated using the ENCODE and RegulomeDB databases and published eQTL dataset of primary immune cells. RESULTS: A genome-wide significant association was discovered at rs1408944 (OR(combined)=1.18, p(combined)=1.38E-09) that locates at a DNAse hypersensitivity site and within a Myb_1 motif carried by the binding sites of six overlapping transcription factors (TFs) within the region. Gene Relationships Across Implicated Loci (GRAIL) analysis revealed biological connectivity between ZMIZ1 and previously discovered susceptibility loci for vitiligo as well as the six TFs. CONCLUSIONS: Our study has confirmed ZMIZ1 as a novel susceptibility locus for vitiligo and further suggested rs1408944 to be the putative causal variant that potentially interrupts TF binding and thus the transcriptional regulation of ZMIZ1.

Genetic variants at 13q12.12 are associated with high myopia in the Han Chinese population.

High myopia, which is extremely prevalent in the Chinese population, is one of the leading causes of blindness in the world. Genetic factors play a critical role in the development of the condition. To identify the genetic variants associated with high myopia in the Han Chinese, we conducted a genome-wide association study (GWAS) of 493,947 SNPs in 1088 individuals (419 cases and 669 controls) from a Han Chinese cohort and followed up on signals that were associated with p < 1.0 × 10(-4) in three independent cohorts (combined, 2803 cases and 5642 controls). We identified a significant association between high myopia and a variant at 13q12.12 (rs9318086, combined p = 1.91 × 10(-16), heterozygous odds ratio = 1.32, and homozygous odds ratio = 1.64). Furthermore, five additional SNPs (rs9510902, rs3794338, rs1886970, rs7325450, and rs7331047) in the same linkage disequilibrium (LD) block with rs9318086 also proved to be significantly associated with high myopia in the Han Chinese population; p values ranged from 5.46 × 10(-11) to 6.16 × 10(-16). This associated locus contains three genes-MIPEP, C1QTNF9B-AS1, and C1QTNF9B. MIPEP and C1QTNF9B were found to be expressed in the retina and retinal pigment epithelium (RPE) and are more likely than C1QTNF9B-AS1 to be associated with high myopia given the evidence of retinal signaling that controls eye growth. Our results suggest that the variants at 13q12.12 are associated with high myopia.

A Case of Superficial Kaposiform Hemangioendothelioma Treated with Oral Propranolol Combined with Topical Sirolimus.

Kaposiform hemangioendothelioma(KHE) without Kasabach-Merritt phenomenon is a rare tumor primarily observed in pediatric patients; however, its documentation in the literature remains limited. We reported about a 1-year-old boy diagnosed with superficial KHE who received oral propranolol in combination with topical sirolimus and reviewed relevant reports and treatment of superficial KHE.

A pediatric case of dupilumab-induced pustular psoriasis.

Dupilumab is a novel treatment agent for moderate to severe atopic dermatitis (AD) with few adverse effects. Drug-induced psoriasiform lesions are rare.We report a 4-year-old boy with AD who developed pustular psoriasis during treatment with dupilumab.Pustular psoriasis appeared within 1 week of treatment and worsened in the second week. After stopping dupilumab administration, topical corticosteroids (desonide and mometasone furoate creams) and oral desloratadine without relief. Pustular psoriasis was confirmed by pathological examination, and thiamphenicol was administered. After 2 weeks of treatment, the lesions nearly resolved without recurrence in 1-year follow-up.Dupilumab-induced pustular psoriasis is rare in children.

Confirmation of C4 gene copy number variation and the association with systemic lupus erythematosus in Chinese Han population.

The distribution of complement component 4 (C4) gene copy number (GCN) has been validated in European populations. Meanwhile, C4 gene has been identified as a susceptibility gene for systemic lupus erythematosus (SLE). However, the association and the possible phenotype significance remain to be determined intensely in the Chinese population. This study was designed to validate the distribution of C4 GCNs in Chinese Han and the correlation between C4 GCNs and SLE using quantitative real-time polymerase chain reaction in 924 SLE patients and 1,007 controls. The results presented distribution of C4 GCNs in healthy populations and also showed that lower C4 GCN was a risk factor for SLE and higher C4 GCN was a protective factor against the disease susceptibility, which was similar to the report in the Caucasian population. Furthermore, we found the association between C4A GCN and disease subphenotypes of arthritis with SLE. We conclude that the association of C4 GCN with SLE was replicated in Chinese Han population, which highlighted the importance of C4 in SLE pathogenesis of diverse populations.

Genetic variation of promoter sequence modulates XBP1 expression and genetic risk for vitiligo.

Our previous genome-wide linkage analysis identified a susceptibility locus for generalized vitiligo on 22q12. To search for susceptibility genes within the locus, we investigated a biological candidate gene, X-box binding protein 1(XBP1). First, we sequenced all the exons, exon-intron boundaries as well as some 5' and 3' flanking sequences of XBP1 in 319 cases and 294 controls of Chinese Hans. Of the 8 common variants identified, the significant association was observed at rs2269577 (p_(trend) = 0.007, OR = 1.36, 95% CI = 1.09-1.71), a putative regulatory polymorphism within the promoter region of XBP1. We then sequenced the variant in an additional 365 cases and 404 controls and found supporting evidence for the association (p_(trend) = 0.008, OR = 1.31, 95% CI = 1.07-1.59). To further validate the association, we genotyped the variant in another independent sample of 1,402 cases and 1,288 controls, including 94 parent-child trios, and confirmed the association by both case-control analysis (p_(trend) = 0.003, OR = 1.18, 95% CI = 1.06-1.32) and the family-based transmission disequilibrium test (TDT, p = 0.005, OR = 1.93, 95% CI = 1.21-3.07). The analysis of the combined 2,086 cases and 1,986 controls provided highly significant evidence for the association (p_(trend) = 2.94x10(-6), OR = 1.23, 95% CI = 1.13-1.35). Furthermore, we also found suggestive epistatic effect between rs2269577 and HLA-DRB1*07 allele on the development of vitiligo (p = 0.033). Our subsequent functional study showed that the risk-associated C allele of rs2269577 had a stronger promoter activity than the non-risk G allele, and there was an elevated expression of XBP1 in the lesional skins of patients carrying the risk-associated C allele. Therefore, our study has demonstrated that the transcriptional modulation of XBP1 expression by a germ-line regulatory polymorphism has an impact on the development of vitiligo.

Clinical Characteristics and In Silico Analysis of Cystinuria Caused by a Novel SLC3A1 Mutation.

Cystinuria is a genetically inherited disorder of renal and intestinal transport, featured as a high concentration of cystine in the urine. Cumulative cystine in urine would cause the formation of kidney stones, which further leads to renal colic and dysfunction. Gene screens have found that mutations in SLC3A1 or SLC7A9 gene are responsible for most cases of cystinuria, for encoding defective cystine transporters. Here, we presented the genotypic and phenotypic characteristics of one unique case of a three-generation Chinese family. The proband developed severe urolithiasis combined with renal damage. The radiography and computed tomography (CT) scan showed calculus in the left pelvic kidney. Postoperative stone analysis revealed that the stones were mainly composed of cystine. Therefore, to explore its pathogenesis, next-generation Whole Exome Sequencing (WES) and Sanger sequencing identify the proband mutated gene of the proband's family. In this article, we reported novel compound heterozygous mutations (c.818G>A and c.1011G>A) of the SLC3A1 gene in a 5-year-old child suffering from a cystine stone from a three-generation family. Bioinformatic analysis was used to predict the pathogenicity and conservation of the target mutation. Conservative sequence and evolutionary conservation analysis indicated that cystine273 and proline337 were highly conserved among species, and both mutations listed here (Cys273Tyr and Pro337Pro) were pathogenic. To conclude, our study expands the phenotypic and genotypic spectrum of SLC3A1 and indicates that genetic screening should be considered in the clinic to provide more effective and precise treatment for cystinuria.

Genome-wide association analysis of anti-TNF-α treatment response in Chinese patients with psoriasis.

Background: TNF-α inhibitors are effective biological agents for treating psoriasis, but the treatment responses differ across patients. This study aimed to identify genetic biomarkers of anti-TNF-α response in Chinese psoriasis patients using a genome-wide association approach. Methods: We recruited two independent cohorts of Chinese psoriasis patients administered etanercept biosimilar (with or without methotrexate). We identified 61 and 87 good responders (PASI improvement ≥75%), 19 and 10 poor responders (PASI improvement <50%) after 24 weeks treatment in the two cohorts, respectively. Then we performed genome-wide association studies (GWAS) on anti-TNF-α response in each cohort independently, followed by a fixed-effects inverse-variance meta-analysis in the 148 good and 29 poor responders. Results: We tested genetic associations with >3 million genetic variants in either cohort. Meta-analysis identified significant associations within seven loci at p < 10-5, which also showed consistent association evidence in the two cohorts. These seven loci include rs2431355 (OR = 6.65, p = 4.46 × 10-7, IQGAP2-F2RL2 on 5q13.3), rs11801616 (OR = 0.11, p = 1.75 × 10-6, SDC3 on 1p35.2), rs3754679 (OR = 0.17, p = 7.71 × 10-6, CNOT11 on 2q11.2), rs13166823 (OR = 0.09, p = 3.71 × 10-6, IRF1-AS1 on 5q31.1), rs10220768 (OR = 5.49, p = 1.48 × 10-6, NPAP1 on 15q11.2), rs4796752 (OR = 5.56, p = 1.49 × 10-6, KRT31 on 17q21.2), and rs13045590 (OR = 0.08, p = 9.67 × 10-7, CTSZ on 20q13.3). Of the seven SNPs, six SNPs showed significant eQTL effect (p < 1 × 10-6) for several genes in multiple tissues. Conclusion: These results suggest novel biological mechanisms and potential biomarkers for the response to anti-TNF therapies. These findings warrant further validation.

Causal Associations between Vitamin D Levels and Psoriasis, Atopic Dermatitis, and Vitiligo: A Bidirectional Two-Sample Mendelian Randomization Analysis.

BACKGROUND: Vitamin D level has been reported to be associated with psoriasis, atopic dermatitis, and vitiligo. However, its causal relationship with the risk of these three diseases remains unclear. METHODS: We obtained genome-wide association statistics for three measures of circulating vitamin D levels (25(OH)D in 120,618 individuals, and 25(OH)D3 and epimeric form C3-epi-25(OH)D3 in 40,562 individuals) and for the diseases psoriasis (3871 cases and 333,288 controls), atopic dermatitis (21,399 cases and 95,464 controls), and vitiligo (4680 cases and 39,586 controls). We performed Mendelian randomization using inverse-variance weighted, weighted median, MR-Egger, and MR-pleiotropy residual sum and outlier methods. We carried out sensitivity analyses to evaluate the robustness of the results. RESULTS: We showed that elevated vitamin D levels protected individuals from developing psoriasis (OR = 0.995, p = 8.84 × 10-4 for 25(OH)D; OR = 0.997, p = 1.81 × 10-3 for 25(OH)D3; and OR = 0.998, p = 0.044 for C3-epi-25(OH)D3). Genetically predicted risk of atopic dermatitis increased the levels of 25(OH)D (OR = 1.040, p = 7.14 × 10-4) and 25(OH)D3 (OR = 1.208, p = 0.048). A sensitivity analysis suggested the robustness of these causal associations. CONCLUSIONS: This study reported causal relationships between circulating vitamin D levels and the risk of psoriasis, atopic dermatitis, and vitiligo. These findings provide potential disease intervention and monitoring targets.

Discovery of Novel Genetic Risk Loci for Acute Central Serous Chorioretinopathy and Genetic Pleiotropic Effect With Age-Related Macular Degeneration.

BACKGROUND: Central serous chorioretinopathy (CSC) is a severe and heterogeneous chorioretinal disorder. Shared clinical manifestations between CSC and age-related macular degeneration (AMD) and the confirmation of CFH as genetic risk locus for both CSC and AMD suggest possible common pathophysiologic mechanisms between two diseases. METHODS: To advance the understanding of genetic susceptibility of CSC and further investigate genetic pleiotropy between CSC and AMD, we performed genetic association analysis of 38 AMD-associated single nucleotide polymorphisms (SNPs) in a Chinese CSC cohort, consisting of 464 patients and 548 matched healthy controls. RESULTS: Twelve SNPs were found to be associated with CSC at nominal significance (p < 0.05), and four SNPs on chromosomes 1, 4, and 15 showed strong associations whose evidences surpassed Bonferroni (BF)-corrected significance [rs1410996, odds ratios (OR) = 1.47, p = 2.37 × 10-5; rs1329428, OR = 1.40, p = 3.32 × 10-4; rs4698775, OR = 1.45, p = 2.20 × 10-4; and rs2043085, OR = 1.44, p = 1.91 × 10-4]. While the genetic risk effects of rs1410996 and rs1329428 (within the well-established locus CFH) are correlated (due to high LD), rs4698775 on chromosome 4 and rs2043085 on chromosome 15 are novel risk loci for CSC. Polygenetic risk score (PRS) constructed by using three independent SNPs (rs1410996, rs4698775, and rs2043085) showed highly significant association with CSC (p = 2.10 × 10-7), with the top 10% of subjects with high PRS showing 6.39 times higher risk than the bottom 10% of subjects with lowest PRS. Three SNPs were also found to be associated with clinic manifestations of CSC patients. In addition, by comparing the genetic effects (ORs) of these 38 SNPs between CSC and AMD, our study revealed significant, but complex genetic pleiotropic effect between the two diseases. CONCLUSION: By discovering two novel genetic risk loci and revealing significant genetic pleiotropic effect between CSC and AMD, the current study has provided novel insights into the role of genetic composition in the pathogenesis of CSC.

Platelet-derived growth factor receptor alpha gene mutations in vitiligo vulgaris.

Vitiligo vulgaris is an acquired depigmenting disorder resulting from the loss of melanocytes in the skin. Though several putative susceptibility loci of vitiligo have been identified in different populations, the pathogenesis of the disease remains poorly understood. Through genetic linkage analysis of a large Chinese family cohort of vitiligo, we identified a vitiligo linkage locus AIS4 within chromosome 4q12-q21, a region containing several possible candidate genes, including the platelet-derived growth factor receptor alpha (PDGFRA) gene. We postulated that PDGFR mutations may be linked with vitiligo. To test this hypothesis, we performed DNA sequencing on this gene in 143 multiplex families with familial vitiligo vulgaris, 480 patients with sporadic vitiligo vulgaris, and 480 healthy subjects. Mutations were found in 3.5% of familial vitiligo cases, which is significantly higher than for the general population (0.42%, p = 0.008, Fisher's exact test), and possibly higher than in sporadic vitiligo patients (1.0%, p = 0.053). To our knowledge, this is the first observation that PDGFRA mutations are linked with familial vitiligo vulgaris.

Epigenomic and genomic analysis of transcriptome modulation in skin cutaneous melanoma.

Skin cutaneous melanoma (SKCM) is characterized by both epigenetic DNA methylation (MET) abnormalities and genomic copy number variations (CNVs). The resulting transcriptome dysregulation promotes progression of many cancers. In this study, DNA copy numbers and MET, as well as mRNA expression, were examined in 466 SKCM samples from The Cancer Genome Atlas. Our results indicate that CNVs-correlated (CNVcor) genes and MET-correlated (METcor) genes are coregulated to a remarkable degree. In addition, integrative multi-omics analysis of both METcor and CNVcor genes revealed four SKCM subtypes with differing prognoses; these subtypes were validated with independent data. Immune cell scores were markedly elevated in the iC1 subtype, which had the best prognosis. Immune cell infiltration correlated with DNA MET or CNV level in SKCM. In the iC3 subtype, which was associated with the most aggressive SKCM cases, FAM135B gene mutation frequencies were increased, while CD8A, GBP5, KIAA0040, and SAMHD1 expression were downregulated, suggesting that these genes play important roles in cancer development and immune responses. Taken together, the results of our epigenetic and genomic transcriptome modulation analysis improve our understanding of SKCM pathobiology and may aid in the development of more effective therapies.

Anti-TNF- αtreatment-related pathways and biomarkers revealed by transcriptome analysis in Chinese psoriasis patients.

BACKGROUND: Anti-tumor necrosis factor alpha (TNF- α) therapy has made a significant impact on treating psoriasis. Despite these agents being designed to block TNF- α activity, their mechanism of action in the remission of psoriasis is still not fully understood at the molecular level. RESULTS: To better understand the molecular mechanisms of Anti-TNF- α therapy, we analysed the global gene expression profile (using mRNA microarray) in peripheral blood mononuclear cells (PBMCs) that were collected from 6 psoriasis patients before and 12 weeks after the treatment of etanercept. First, we identified 176 differentially expressed genes (DEGs) before and after treatment by using paired t-test. Then, we constructed the gene co-expression modules by weighted correlation network analysis (WGCNA), and 22 co-expression modules were found to be significantly correlated with treatment response. Of these 176 DEGs, 79 DEGs (M_DEGs) were the members of these 22 co-expression modules. Of the 287 GO functional processes and pathways that were enriched for these 79 M_DEGs, we identified 30 pathways whose overall gene expression activities were significantly correlated with treatment response. Of the original 176 DEGs, 19 (GO_DEGs) were found to be the members of these 30 pathways, whose expression profiles showed clear discrimination before and after treatment. As expected, of the biological processes and functionalities implicated by these 30 treatment response-related pathways, the inflammation and immune response was the top pathway in response to etanercept treatment, and some known TNF- α related pathways, such as molting cycle process, hair cycle process, skin epidermis development, regulation of hair follicle development, were implicated. Furthermore, additional novel pathways were also suggested, such as heparan sulfate proteoglycan metabolic process, vascular endothelial growth factor production, whose transcriptional regulation may mediate the response to etanercept treatment. CONCLUSION: Through global gene expression analysis in PBMC of psoriasis patient and subsequent co-expression module based pathway analyses, we have identified a group of functionally coherent and differentially expressed genes (DEGs) and related pathways, which has not only provided new biological insight about the molecular mechanism of anti-TNF- α treatment, but also identified several genes whose expression profiles can be used as potential biomarkers for anti-TNF- α treatment response in psoriasis.