The first genome wide association scan on psoriasis was published
Jan. 25 in Nature Genetics online. Dr. Proton Rahman, of Memorial’s Faculty of Medicine, is one of the authors of the study which genotyped over 438,000 markers scattered across the entire genome.
This large multinational effort was led by Dr. J.T. Elder at the University of Michigan. Memorial was one of two Canadian centres to participate in this study.
Dr. Rahman said that other than identifying existing genes known to be associated in psoriasis, this study also identified genes that regulate cytokine signaling and modulate immune responses in psoriasis.
“This study also implicated numerous candidate genes in psoriatic arthritis that are actively being screened here at Memorial and at the University of Michigan,” he said.
Psoriasis is a common immune-mediated disorder that affects the skin, nails and joints. To identify psoriasis susceptibility loci, the researchers genotyped 438,670 SNPs (single nucleotide polymorphisms) in 1,409 psoriasis cases and 1.436 controls of European ancestry. They followed up 21 promising SNPs in 5,048 psoriasis cases and 5,041 controls. “Results provide strong support for the association of at least seven genetic loci and psoriasis,” said Dr. Rahman. “These results expand the catalog of genetic loci implicated in psoriasis susceptibility and suggest priority targets for study in other auto-immune disorders.”
Funding for this research came from the National Institutes of Health, the Foundation for NIH’s Genetic Association Information Network and the National Psoriasis Foundation. Analysis and genotyping of follow-up samples was also supported by the German National Genome Research Network, the Canadian Institute of Health Research and the Arthritis Society of Canada, the Centre National de Génotypage, Généthon and the Association Française contre les Myopathies, and by Celera Corporation.