Psoriasis 12, Susceptibility To

For a phenotypic description and a discussion of genetic heterogeneity of psoriasis, see PSORS1 (177900).

Mapping

In a genomewide association study involving 318 British patients with psoriasis and 288 controls, Capon et al. (2008) found an association between psoriasis and rs495337 on chromosome 20q13 (p = 4.5 x 10(-5)). The findings were replicated in a second British cohort of 1,429 patients, and a third German cohort of 932 patients, yielding an overall combined p value of 1.4 x 10(-8). The SNP maps to a region of the genome in linkage disequilibrium with RNF114 (612451), which is expressed in skin, T lymphocytes, and dendritic cells.

Onoufriadis et al. (2012) analyzed the RNF114 gene in 485 psoriasis patients and 842 controls and identified 4 disease-associated variants in the RNF114 promoter, each of which was present in a single patient. Electrophoretic mobility shift analysis showed that 2 of the variants, -41C-T and -64C-A, were associated with reduced SP1 (189906)-binding activity and reduced RNF114 gene expression.