The role of GNLY gene polymorphisms in psoriasis pathogenesis

BACKGROUND: Psoriasis is a systemic inflammatory disorder that involves complex pathogenic interactions between the innate and adaptive immune systems. The most accepted mechanism in the etiopathogenesis of psoriasis is the induction of inflammation with keratinocyte hyperproliferation. Granulysin (GNLY) is a cytolytic antimicrobial peptide (AMP) that is secreted together with granzyme and perforin from the granules of human cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells. It has been immunohistochemically proven that the expression of granulysin is increased in lesions of psoriasis. OBJECTIVE: This study aimed to investigate the relationship between psoriasis disease and granulysin gene polymorphisms. METHODS: GNLY rs7908 and rs10180391 polymorphisms were studied by PCR-RFLP in 100 psoriasis patients under treatment in the Dermatology Polyclinic of Bulent Ecevit University. In addition, 100 healthy individuals with similar age and sex distribution were used as a control group. RESULTS: In the control group, GNLY rs7908 CC genotype was significantly higher than in psoriasis patients (P= 0.031; OR= 0.305; Cl= 0.305 (0.121 - 0.773). In our study, the genotype distributions in patients and control groups were GNLY rs7908 (SNP) GG (51%, 37%), GC (41%, 44%), CC (8%, 19%); GNLY rs10180391 (SNP) from the CC (41%, 44%), CT (42%, % 41), TT (17%, 15%). STUDY LIMITATIONS: The study only included Turkish patients. CONCLUSION: Our findings showed that GNLY rs7908 CC genotype and C allele had a protective effect against psoriasis and decreased the disease severity (according to PASI score), whereas rs10180391 SNP did not show any effective role in psoriasis pathogenesis.