Common European mitochondrial haplogroups in the risk for psoriasis and psoriatic arthritis.

Mitochondrial dysfunction could contribute to the pathogenesis of psoriasis (Ps) and Ps-arthritis (PsA). Several common mtDNA polymorphisms/haplogroups have been linked to differences in the production of reactive oxygen species and mitochondrial oxidative damage. To test the hypothesis of an association between mtDNA variants and Ps/PsA, we studied the single-nucleotide polymorphisms that define the common European haplogroups in a total of 325 patients and 300 controls from Spain. No allele/haplogroup was significantly associated with the risk for Ps. However, haplogroup J was significantly less frequent among patients with PsA, suggesting a protective effect in our population (p=0.04; odds ratio=0.39). We concluded that mtDNA may have a role in Ps and PsA.