Treating Psoriasis: The Pharmacogenomic Approach

A total of 293 patients with plaque psoriasis, 82 patients with psoriasis guttata and 202 control subjects were enrolled in this study. Investigations focused on 3 polymorphisms in retinoid X receptors RXRA and RXRB gene associations. The possible association of their variability with psoriasis was investigated.

A marginally significant increase in AA allelic frequency of the RXRA A39526AA polymorphism in plaque psoriatic men compared to healthy ones was proven. In women with psoriasis guttata, a higher risk for genotypes AA and TT in the RXRB 3'+140A/T polymorphism compared to healthy women was identified. The genotypes A/A and AA/AA were more frequent in plaque psoriasis patients with a positive family history of psoriasis compared to patients with a negative family history of psoriasis. The A/A genotype was more frequent in patients with plaque psoriasis and repeated tonsillitis/tonsillectomy. In the RXRB polymorphism, no genotype TT was observed in patients with psoriasis guttata with a positive personal history of repeated tonsillitis.

Accordingly, these two RXR polymorphisms seem to be susceptibility genes for psoriasis. This knowledge contributes to improving the results of psoriasis therapy using a pharmacogenomic approach.