Abstracto

Effects of serum paraoxonase and paraoxonase phenotypic distribution on the parameters of first trimester screening

Ayla Kilic, Mehmet Ozen, Onur Erol, Hamit Yasar Ellidag, Fatma Demet Arslan Ince, Esin Eren, Necat Yilmaz

Background: First trimester screening is a program used to identify any chromosome abnormalities in the first trimester of pregnancy by combining ultrasonography and biochemical markers. The aim of this study is to analyse the relationship between ultrasonography (NT, CRL) and biochemical markers (PAPP-A, β-hCG) with the levels of paraoxonase (PON1), a multifunctional enzyme associated with High-Density Lipoprotein (HDL) and Arylesterase (ARE)-level PON1 phenotypic distribution which are the parameters used in the first trimester screening program.

Materials and Methods: Included in the study were pregnant women (n=114) in weeks 11-13 of pregnancy who had undergone first trimester screening tests. Risks were determined through the use of Benetech PRA software, Serum PON1, ARE and stPON1 values were analysed, and PON1 phenotypic distribution was determined through the double substrate method.

Results: No significant correlation was found between the results of the PON1 and ARE activities and the first trimester screening parameters. The Q allele frequency of the study group was 0.787, while the R allele frequency was 0.213. The PON1 phenotype distributions of the pregnant women were as follows: 66 (58%) QQ, 45 (39.4%) QR and 3 (2.6%) RR phenotypes respectively.

Conclusion: There is a need for more advanced studies to evaluate the relationship between the serum PON1, ARE and PON1 phenotypic distributions of pregnant women in their first trimesters with the complications that may develop in later stages of pregnancy.