Human paraoxonase (PON) is an enzyme involved in vasodilation and thrombosis. Disruption of blood blow through the placenta could be part of the pathophysiological mechanism leading to preterm delivery. The purpose of this study was to examine the association between polymorphisms in 2 paraoxonase genes (PON1 and PON2) and preterm delivery.Methods:
We conducted a case-control study using infant-parents triads in Anqing, China. Between July 1999 and June 2001, we enrolled the families of 105 infants born at term and 80 infants born preterm. Genotyping was performed for the polymorphisms of PON1 Q192R, PON2 A148G, and PON2 S311C using standard techniques. We used log-linear modeling to analyze the association of PON1 and PON2 gene polymorphisms with the risk of preterm delivery.Results:
In the analysis of children’s genotypes, the relative risk was 3.6 (95% confidence interval [CI] = 1.3–11) for PON1 RR compared with PON1 QQ. An association was also seen for PON2 CC compared with PON2 SS (relative risk = 4.6; CI = 1.5–14). There was no association between the mother’s PON1 and PON2 genotypes and preterm delivery, and we did not observe an interaction between mothers’ and children’s genotypes. Analysis of control triads suggests Mendelian transmissions of the variant alleles of PON1 192R, PON2 148G, and PON2 311C.Conclusion:
Infant PON1 RR and PON2 CC genotypes were associated with preterm delivery in our study population, which suggests a possible role for human paraoxonase variability in the etiology of preterm delivery.