Genetic association analysis is a major tool for identifying disease susceptibility variants that contribute to a specific disease or phenotype. The use of association analysis depends either on prior biological knowledge that points to particular polymorphisms in candidate genes, or requires a very high density of genetic markers in genomic regions.
Genome wide association studies (GWAS) resemble classical association analyses with alleles at genetic markers representing putative risk factors. GWAS provide an unbiased, genome-wide search and have become the standard tool for discovery of genetic loci implicated in human diseases. Hundreds of common single nucleotide polymorphisms (SNPs) whose allele frequencies are statistically correlated with common diseases such as autoimmune or inflammatory diseases have been published.
At our institute, we have performed genetic association analyses/GWAS studies for several inflammatory diseases, like Crohn’s disease, ulcerative colitis, primary sclerosing cholangitis, psoriasis, atopic dermatitis, sarcoidosis and common variable immune deficiency and several of our group members belong to international consortia, like the International IBD Genetics Consortium (IIBDGC), the International PSC Study Group (IPSCSG), and the Psoriasis Association Genetics Extension (PAGE).