title: Addressing the link between paraoxonase-1 gene variants and the incidence of early onset myocardial infarction.
abstract: BACKGROUND
  The enzyme paraoxonase-1 (PON1) represents an endogenous defense mechanism against vascular oxidative stress, thereby contributing to the prevention of atherosclerosis. Several polymorphisms have been reported in the PON1 gene, including Q192R. PON1 phenotype is commonly expressed as the paraoxonase/arylesterase ratio (PON/ARE). The major aim of this study was to investigate the association between PON1 Q192R polymorphism, PON1 phenotypes and the incidence of early-onset acute myocardial infarction (AMI) in Egyptians.
  
  
  METHODS
  The study subjects consisted of 102 AMI patients and 72 age-matched healthy controls. Genotyping and enzyme activities were determined using PCR-RFLP and kinetic spectrophotometric assays, respectively.
  
  
  RESULTS
  The genotype distribution for the PON1 gene was significantly different between AMI patients (QQ = 38.24%, QR = 49.02%, RR = 12.75%) and controls (QQ = 66.67%, QR = 25%, RR = 8.33%). Allele frequencies were also significantly different between patients (Q = 62.75%, R = 37.25%) and controls (Q = 79.17%, R = 20.83%). The genotypes QR and RR showed higher risk for AMI compared to the homozygous QQ (odds ratio (OR) = 3.231, p < 0.001). The average PON/ARE ratio in MI patients (1.187 ±0.1) did not differ significantly from controls (1.118 ±0.26). However, it showed a significant difference among different genotypes in both AMI patients (QQ = 0.91 ±0.11, QR = 1.09 ±0.11 and RR = 2.65 ±0.4) (p = 0.0002) and controls (QQ = 0.68 ±0.1, QR = 1.07 ±0.11 and RR = 4.89 ±2.84) (p < 0.0001).
  
  
  CONCLUSIONS
  PON1 192R allele represents an independent risk factor for early-onset AMI in Egyptians, and PON1 Q192R polymorphism modulates the paraoxonase phenotype.
authors.affiliation: Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, German University, Cairo, Egypt.
authors.forename: Mohamed F Abdel
authors.initials: MF
authors.lastname: Rahman
authors.affiliation: Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, German University, Cairo, Egypt.
authors.forename: Ingy M
authors.initials: IM
authors.lastname: Hashad
authors.affiliation: Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, German University, Cairo, Egypt.
authors.forename: Khaled
authors.initials: K
authors.lastname: Abou-Aisha
authors.affiliation: Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, German University, Cairo, Egypt.
authors.forename: Sahar M
authors.initials: SM
authors.lastname: Abdel-Maksoud
authors.affiliation: Clinical Biochemistry Unit, Faculty of Pharmacy and Biotechnology, German University, Cairo, Egypt.
authors.forename: Mohamed Z
authors.initials: MZ
authors.lastname: Gad
keywords: Egyptians; PON polymorphism; acute myocardial infarction; arylesterase; paraoxonase