Role of tissue plasminogen activator and plasminogen activator inhibitor polymorphism in myocardial infarction

A case–control association study on 229 Myocardial Infarction (MI) patients and 217 healthy controls was carried out to determine the role of tissue-plasminogen activator (t-PA) (Alu-repeat insertion (I)/deletion (D)) and plasminogen activator inhibitor (PAI-1) (4G/5G insertion/deletion) polymorphisms with MI in the Pakistani population. In MI patients the genotype distribution of the PAI-1 gene was not found to be different when compared with the unaffected controls (P > 0.05, χ² = 1.03). The risk allele 4G was also not associated with MI (P > 0.05, χ² = 0.46, odds ratio (OR) = 1.1 (95% confidence interval (CI) = 0.84–1.43), P > 0.05). Similarly, the genotype frequencies of t-PA I/I, I/D and D/D were not different from the unaffected controls (P > 0.05, χ² = 1.60), and the risk allele “I” was not found to be associated with MI (P > 0.05, χ² = 1.35, OR = 0.86 (95% CI = 0.66–1.11), P > 0.05). However, when the data were distributed along the lines of gender a significant association of the 4G/4G PAI-1 genotype was observed with only the female MI patients (P < 0.05, z-test = 2.21). When the combined genotypes of both the polymorphisms were analyzed, a significant association of MI was observed with the homozygous DD/4G4G genotype (P < 0.01, z-test = 2.61), which was specifically because of the female samples (P = 0.01, z-test = 2.53). In addition smoking (P < 0.001, χ² = 13.52, OR = 3.45 (95% CI = 1.77–6.94)), diabetes (P < 0.001, χ² = 22.45, OR = 8.89 (95% CI = 2.96–29.95)), hypertension (OR = 7.76 (95% CI = 2.88–22.68), P < 0.001) family history (P < 0.001, χ² = 13.72, OR = 3.7 (95% CI = 1.71–8.18)) and lower HDL levels (P < 0.05) were found to be significantly associated with the disease. In conclusion the PAI-1 gene polymorphism was found to have a gender specific role in the female MI patients.