Genetic variants associated with increased susceptibility to psoriasis are reported in five papers published online this week in Nature Genetics. Psoriasis is a chronic and recurrent skin disease, and one of the most prevalent autoimmune diseases, with a global prevalence of 2-3%.

Richard Trembath and colleagues report a genome-wide association study in 2,622 psoriasis cases and 5,667 healthy controls in the UK, with replication in over 9,000 individuals from European studies. They identify six genomic regions newly associated with psoriasis, and find evidence for an interaction between two associated regions.

Andre Franke, Andre Reis, and their respective colleagues report independent psoriasis genome-wide association studies in German populations. They each identify genetic variants in the gene TRAF3IP2 associated with psoriasis.

James Elder and colleagues report meta-analysis of two recent genome-wide association studies for psoriasis, identifying three genomic regions newly associated with psoriasis.

Xue-Jun Zhang and colleagues report association analyses in a Chinese population, identifying six genomic regions newly associated with psoriasis. Their comparison with the findings in European studies highlights the heterogeneity in psoriasis genetic susceptibility factors between populations.