The Role of Apurinic/Apyrimidinic Endonuclease DNA Repair Gene in Endometriosis

Background/Aim: The altered cellular repair capacity plays a critical role in genomic instability and carcinogenesis. We aimed at evaluating the contribution of the polymorphic variant in apurinic/apyriminidinic endonuclease (APEX1) gene to its mRNA and protein levels and the risk of endometriosis. Patients and Methods: In the current case-control study, 153 endometriosis patients and 636 non-endometriosis controls were recruited. APEX1 Asp(148)Glu (rs1130409) genotyping was conducted by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). At the same time, twenty eight endometriosis tissue samples with different genotypes were examined regarding their expression levels of APEX1 mRNA and protein by quantitative reverse transcription-polymerase chain reaction (q-PCR) and western blotting, respectively. Results: Compared with wild-type TT genotype, TG and GG genotypes of APEX1 Asp(148)Glu had a risk of endometriosis of 0.93- and 0.87-fold. The results from in vivo transcriptional (RNA) and translational (protein) level analysis revealed that the APEX1 mRNA and protein were of similar levels among the endometriosis tissues of people carrying TT, TG, or GG genotypes. There was no joint effect of APEX1 Asp(148)Glu genotype with menarche, pregnancy, smoking or alcohol drinking lifestyles on endometriosis risk. Conclusion: The APEX1 Asp(148)Glu genotype correlates well with its mRNA and protein expression among endometriosis patients and may not serve as a sensitive marker for prediction of endometriosis risk in Taiwan.