Collagen XVIII and LOXL-4 polymorphisms in women with and without advanced pelvic organ prolapse

Introduction and hypothesis We verified the presence of single nucleotide polymorphisms (SNP) rs2236479 of the collagen 18 ( COL18A1 ) and rs2862296 of the lysyl oxidase-like 4 ( LOXL-4 ) genes and the association with pelvic organ prolapse (POP) in Brazilian women and determined risk factors for POP development. Methods We assessed 532 postmenopausal women divided into POP (stages III and IV) and control (stages 0 and I) groups by examination and peripheral blood sample collection. DNA sequences of interest were analyzed by real-time reverse-transcriptase polymerase chain reaction (RT-PCR). We used logistic regression models for the analyses, with p < 0.005 for significance. Results The frequency of homozygous polymorphic alleles (AA) in COL18A1 and (GG) in LOXL-4 were similar in both groups (17.5% and 15.4% for COL18A1 and 18.9% and 20.6% for LOXL-4 , respectively). There were no associations between those polymorphisms or other genotypes and POP. Multiple logistic regression analysis identified age [odds ratio (OR) = 1.10, confidence interval (CI) 95% = 1.07; 1.14), number of vaginal births (OR = 1.66, CI 95% = 1.36; 2.03), and family history (OR = 2.55 CI 95% = 1.43; 4.55) as independent risk factors for POP. Conclusion Our study suggests lack of association between DNA polymorphisms rs2236479 of COL18A1 and rs2862296 of LOXL-4 with advanced POP in this population.