Additionally, we are going to search for polymorphism of promoter region of IL-6 /G-174C also by means of PCR in DNA collected from peripheral blood leukocytes, using prim-ers 5'- AAT CTT TGT TGG AGG GTG AG and 5'- ACA TGC CAA GTG CTG AGT CA and restriction endonuclease Sfa NI on 2% agarose gel.