The paraoxonase L55M and Q192R gene polymorphisms and myocardial infarction in a Tunisian population.

Objectives: In the present study, we examined a possible association between the PON1 Q192R and L55M polymorphisms and myocardial infarction (MI) in a sample of the Tunisian population.

Design And Methods: Three hundred and ten patients with MI and 375 controls were recruited. Paraoxonase gene polymorphisms at codon 192 and 55 were analyzed by PCR-RFLP.

Results: Genotype distributions and allele frequencies of L55M were similar among the control and MI groups. For the Q192R polymorphism patients with MI had significantly higher frequency of the RR genotype compared to controls [17.1% vs. 10.9%; OR (95% CI), 1.93 (1.24-3.02); p=0.004]. The MI patient group showed a significantly higher frequency of the R allele compared to the controls [38% vs. 30%; χ(2)=10.74, p=0.001]. The association between the PON1 Q192R polymorphism and MI remained significant after adjustment for other well-established cardiovascular risk factors.

Conclusions: The present study showed a significant and independent association between the PON1 Q192R polymorphism (presence of R allele) and MI in the Tunisian population.