“Genes such as these are important for determining the pathogenesis of psoriasis and PsA and in identifying novel drug targets for these inflammatory disease of the skin and joints."—Anne Bowcock, PhD.
"Genes such as these are important for determining the pathogenesis of psoriasis and PsA and in identifying novel drug targets for these inflammatory diseases of the skin and joints," conclude researchers led by Anne Bowcock, PhD, professor of genetics at the Washington University School of Medicine in St. Louis, Missouri.Using a whole genome association strategy, the researchers scanned >300,000 SNPs in 223 psoriasis patients including 91 who had PsA. They compared the DNA variations in people with psoriasis to those in 519 healthy controls. They then replicated their findings in a larger set of patients comprising 577 patients with psoriasis, 576 with PsA, and >1200 healthy controls.
The search yielded 7 novel DNA variations linked to psoriasis. Notably, DNA variations on chromosome 4 were strongly linked to PsA. This region is known to harbor interleukin (IL) -2 and -21 genes and has been previously linked to type 1 diabetes, rheumatoid arthritis, Grave’s disease, and celiac disease. The new regions are located on chromosomes 13q13, 15q21, 1q21, 2p11, 2p12, and 3q13. The study also confirmed that genetic variations in the multiple histocompatibility locus antigen cluster are the most important risk factors for psoriasis and play an important role in conferring risk of PsA.
The researchers are conducting larger genome-wide association scans of psoriasis patients to uncover additional genetic variations associated with psoriasis and to confirm some of the variations found in that report.
Translating research into practice
"This comprehensive study of psoriasis and PsA continues to reveal the considerable genetic complexity and overlapping relationships between various autoimmune and inflammatory diseases," said Peter K. Gregersen MD, director of the Robert S. Boas center for genomics and human genetics at the Einstein Institute for Medical Research in Manhasset, New York. "It also emphasizes the need for international collaborations to collect, characterize and follow up on large cohorts of patients in order to fully understand and make use of all this new genetic information."
Reference
1. Liu Y, Helms C, Liao WZ, et al. A genome-wide association study of psoriasis and psoriatic arthritis identifies new disease loci. PLoS Genet. 2008;4:e1000041. doi:10.1371/journal.pgen.1000041. http://www.plosgenetics.org/article/fetchArticle.action?articleURI=info:doi/10.1371/journal.pgen.1000041.
PubMed: Related Articles