Interleukin-1 receptor antagonist and tumour necrosis factor-alpha gene polymorphisms in Turkish patients with allergic contact dermatitis.

BACKGROUND: It has been shown that the family of interleukin-1 receptor antagonist (IL-1 RA) and tumour necrosis factor-alpha (TNFalpha) genes are polymorphic and related to some inflammatory diseases. Allergic contact dermatitis is the classic presentation of delayed-type hypersensitivity responses to exogenous agents. A number of genes playing role in inflammatory response may be associated with allergic contact dermatitis.

OBJECTIVES: To investigate whether there is an association between IL-1RA and TNFalpha gene polymorphisms and allergic contact dermatitis in Turkish patients with allergic contact dermatitis.

METHODS: This study was performed by the collaboration of Departments of Dermatology and Medical Genetics, Ege University, Faculty of Medicine. A total of 50 patients (31 females and 19 males) with allergic contact dermatitis, and 100 age- and sex-matched controls (58 females and 42 males) were included in the study. IL-1RA Variable Number of Tandem Repeats (VNTR) polymorphism in intron 2 and TNFalpha-308G-A polymorphism were genotyped by using polymerase chain reaction and agarose gel electrophoresis.

RESULTS: The frequency of IL-1RA 1/2 (48%) genotype was significantly higher (P = 0.002) in patient group than that is found in control group (22%). The frequency of TNFalpha (TNF G-308A) G/G genotype was significantly higher in patient group (68%) than that is found in control group (31%) (P = 0.008).

CONCLUSIONS: Our findings suggest that TNFalpha (G/G) gene polymorphism may play role in susceptibility to allergic contact dermatitis in Turkish patients.