1. ¹Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
2. ²Third Department of Internal Medicine, Semmelweis University, Budapest, Hungary
3. ³Department of Microbiology and Immunology, University of Tampere, Tampere University Hospital, Tampere, Finland

Correspondence: Dr JP Pandey, Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC 29425-2230, USA. E-mail: pandeyj@musc.edu

Received 12 May 2003; Revised 27 August 2003; Accepted 29 August 2003.

Abstract

Immunoglobulin GM and KM genes have been associated with antibody responses to a variety of antigens. A promoter-region polymorphism of interleukin-6 (IL-6) gene (-174 G/C) has been shown to be associated with antibody responses to heat-shock proteins (hsp) 60 and hsp65. To examine the possible epistatic effects of these unlinked genetic systems on the autoimmune responses to hsp60 and hsp65, 176 healthy Caucasian subjects from Finland were genotyped for several allelic determinants of GM, KM, and IL-6 genes by PCR-RFLP methods. IgG antibodies to hsp60 and hsp65 were measured by an ELISA. Significant interactive effects of GM f,z and IL-6-174 genotypes were noted for both anti-hsp60 (P=0.002) and anti-hsp65 (P=0.038) antibody levels. Since these autoantibodies have been implicated in susceptibility to coronary heart disease and carotid atherosclerosis, the associations reported here might be relevant to the etiology of these diseases.