In this study we investigated the possible role of two CCR5 gene polymorphisms, CCR5Delta32 deletion and CCR5 59029 A-->G promoter point mutation, in determining the susceptibility to Trypanosoma cruzi infection as well as in the development of chagasic heart disease. These CCR5 polymorphisms were assessed in 85 seropositive (asymptomatic, n=53; cardiomyopathic, n=32) and 87 seronegative individuals. The extremely low frequency (0.009) of the CCR5Delta32 allele in our population did not allow us to analyse its possible influence on T. cruzi infection. We found no differences in the distribution of CCR5 59029 promoter genotype or phenotype frequencies between total chagasic patients and controls. However, we observed that the CCR5 59029-A/G genotype was significantly increased in asymptomatic with respect to cardiomyopathic patients (P=0.02; OR=0.33, 95% CI 0.10-0.94). In addition, the presence of the CCR5 59029-G allele was also increased in asymptomatics when compared with cardiomyopathics (P=0.02; OR=0.35, 95% CI 0.12-0.96). Our data suggest that the CCR5 59029 promoter polymorphism may be involved in a differential susceptibility to chagasic cardiomyopathy.