Genome-wide pathway analysis of a genome-wide association study on psoriasis and Behcet's disease.
The aim of this study was to identify candidate causal single nucleotide polymorphisms (SNPs) and candidate causal mechanisms of psoriasis and Behcets's disease (BD) and to generate an SNP → gene → pathway hypothesis. A psoriasis genome-wide association study (GWAS) dataset that included 436,192 SNPs in 1,409 psoriasis cases and 1,436 controls of European descent and a BD GWAS dataset that contained 310,324 SNPs in 1,215 BD cases and 1,278 controls were used in this study. Identify candidate causal SNPs and pathways (ICSNPathway) analysis was applied to the GWAS datasets. ICSNPathway analysis identified 15 candidate causal SNPs and 28 candidate causal pathways. The top five candidate causal SNPs were rs1063478 (P = 1.45E-10), rs8084 (P = 2.20E-08), rs7192 (P = 5.18E-08), rs20541 (P = 5.30E-06), and rs1130838 (P = 5.65E-06), which with the exception of rs20541 [interleukin (IL)-13] are at human leukocyte antigen (HLA) loci. These candidate causal SNPs and pathways provided ten hypothetical biological mechanisms. The most strongly associated pathway concerned HLA. When HLA loci were excluded, ICSNPathway analysis provided one hypothetical biological mechanism. rs20541 (non_synonymous_coding) → IL-13 → dendritic cell involvement in the regulation of Th1 and Th2 development, and the GATA3 pathway. ICSNPathway analysis identified four candidate causal SNPs, eleven candidate causal pathways, and three hypothetical biological mechanisms. One of them was as follows: rs2072895 (non_synonymous_coding & splice-site) and rs2735059 (non_synonymous_coding) → HLA-F → type I diabetes mellitus, antigen processing and presentation, and autoimmune thyroid disease. The application of ICSNPathway analysis to GWAS dataset of psoriasis and BD resulted in the identification of candidate causal SNPs and candidate pathways that might contribute to psoriasis susceptibility.
Division of Rheumatology, Department of Internal Medicine, Korea University College of Medicine, Korea University Medical Center, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-705, Korea. lyhcgh@korea.ac.kr
Young Ho
YH
Lee
Sung Jae
SJ
Choi
Jong Dae
JD
Ji
Gwan Gyu
GG
Song
D001528:Behcet Syndrome / Q000150:complications* / Q000235:genetics*; D030541:Databases, Genetic; D056426:Genetic Loci / Q000235:genetics; D020022:Genetic Predisposition to Disease; D015894:Genome, Human / Q000235:genetics*; D055106:Genome-Wide Association Study; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D015810:Linkage Disequilibrium / Q000235:genetics; D015201:Meta-Analysis as Topic; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011565:Psoriasis / Q000150:complications* / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics*
D006680:HLA Antigens