Interleukin-1b (IL-1b) plays an important role in the pathogenesis of atherosclerosis and myocardial infarction (MI). The aim of this study was to test whether the +3953 (C→T) polymorphism of IL-1β gene in exon 5 is associated with MI in Russians and Tatars of Bashkortostan. We examined 306 male patients with MI and 245 healthy controls. Genotype frequencies for IL-1β exon 5 polymor­phisms in Russian controls: 71 E1 homozygotes (61.2%), 40 E1/E2 heterozygotes (34.5%), five E2 homozygotes (4.3%), and in Tatar controls 73 (56.6%), 46 (35.7%) and 10 (7.8%), respectively, and were similar to those reported for North American Caucasian healthy controls. In the MI patients, the genotype frequencies in Russians were 110 E1/E1 (53.9%), 67 E1/E2 (35.1%), 21 E2/E2 (11.0%), and in Tatars 73 (56.6%), 46 (35.7%) and 10 (7.8%), respectively. No significant differences in allele or genotype frequencies were found between the patient and the control groups. In the subgroup of Russian patients with a body mass index (BMI) of ≥25 and left ventricular hypertrophy (LVH), frequencies of the E2 allele and E2/E2 genotype were significantly higher than in the control group. This study shows that the +3953 (C→T) IL-1β gene polymorphism may be a genetic risk factor for the development of MI in Russian patients with a BMI of ≥25 and with LVH.

      Key words: Atherosclerosis; Gene; Interleukin-1β (IL-1β); Myocardial infarction (MI); Polymorphism.