Recent studies have suggested the involvement of increased
reactive oxygen species levels and decreased
antioxidant system functions in
psoriasis pathogenesis. In this study, we aimed to examine to investigate possible associations between the
manganese superoxide dismutase (MnSOD Ala-9Val) and
glutathione peroxidase (GPx1 Pro198Leu) polymorphisms and
psoriasis susceptibility and
disease progression in a Turkish population. The study group consisted of 100 unrelated patients with
psoriasis and 167 unrelated healthy controls. Genomic
DNA was extracted from peripheral leukocytes of whole blood which were obtained from all patients and control subjects. Genotyping was performed to identify MnSOD Ala-9Val and GPx1 Pro198Leu polymorphisms by a method based on PCR amplification and detection of polymorphisms with hybridization probes labeled with
fluorescent dyes. Genotype and allele frequencies were compared between patients with
psoriasis and 106 healthy control subjects. There was no significant difference between the MnSOD Ala-9Val single nucleotide polymorphism (SNP) genotype distributions and allele frequencies of the
psoriasis patients and the control group (p = 0.99 and p = 0.89, respectively). There was also no significant difference between distributions of the genotype or allele frequencies of the GPx1 Pro198Leu SNP of the patient groups and control subjects (p = 0.99 and p = 0.96, respectively). Also, no significant difference was found between clinical severity of
psoriasis and MnSOD Ala-9Val and GPx1 Pro198Leu polymorphism. This is the first report investigating the possible associations between the MnSOD Ala-9Val and GPx1 Pro198Leu polymorphisms and
psoriasis susceptibility and
disease progression in the Turkish population even if no significant difference was found between patient groups and control subjects. Further studies with large cohort on different populations and ethnicities will be able to better clarify the association.