Exome-Wide Rare Loss-of-Function Variant Enrichment Study of 21,347 Han Chinese Individuals Identifies Four Susceptibility Genes for Psoriasis.

Most psoriasis-related genes or loci identified by GWAS represent common clusters and are located in noncoding regions of the human genome, providing only limited evidence for the roles of rare coding variants in psoriasis. Two exome-wide case-control genotyping data sets (11,245 cases and 11,177 controls) were obtained from our previous study. Quality controls were established for each data set, and the markers remaining in each set were annotated using ANNOVAR. Gene-based analysis was performed on the annotation results. A total of 250 and 35 genes in the Exome_Fine and Exome_Asian array cohorts, respectively, exceeded the threshold (P < 4.43 × 10-6). Merged gene-based analysis was then conducted on the same set of SNPs from seven genes common to both arrays, and the chi-square test was used to confirm all gene-based results. Ultimately, four susceptibility genes were identified: BBS7 (Pcombine = 1.38 × 10-29), GSTCD (Pcombine = 8.35 × 10-47), LIPK (Pcombine = 1.02 × 10-19), and PPP4R3B (Pcombine = 1.79 × 10-33). This study identified four susceptibility genes for psoriasis via a gene-based method using rare variants, contributing to our understanding of the pathogenesis of psoriasis.