Genetic Polymorphisms of COL1A1 Promoter Region (rs1800012) and TGFB1 Signal Peptide (rs1800471): Role in Cervical Insufficiency Susceptibility?

A structural or functional cervix problem prevents a woman from carrying a full-term pregnancy, which leads to the disease known as cervical insufficiency. Cervical insufficiency is partially inherited, and in certain situations, variations in genes related to connective tissue metabolism may be involved. The main objective of this investigation was to describe the collagen type I alpha 1 chain (COL1A1) gene rs1800012 polymorphism and the transforming growth factor beta 1 (TGFB1) gene rs1800471 polymorphism in a cohort of patients suffering from cervical insufficiency. Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays have been used to analyze the DNAs of 93 patients with cervical insufficiency and 103 healthy controls. The chi-square test was used for statistical analysis. There were significant differences in the genotype frequencies of the COL1A1 gene rs1800012 (G > T) and TGFB1 gene rs1800471 (G > C) polymorphisms between the patient and the control groups (p = 0.049 and p = 0.049, respectively). Also, the C allele of the TGFB1 rs1800471 polymorphism was significantly higher in the patient group than the control group (p = 0.016). Following clinical assessment, the COL1A1 rs1800012 polymorphism was found to be connected to the history of cerclage (p = 0.010). Additionally, the frequency of the TT/GG composite genotype of COL1A1 rs1800012/TGFB1 rs1800471 polymorphisms was significantly lower in the patient group than the control group (p = 0.049). The TT genotype of COL1A1 rs1800012 polymorphism was found to be protective against cervical insufficiency, while the C allele of TGFB1 rs1800471 polymorphism was found to predispose to the disease. It appears that the TT/GG composite genotype of COL1A1 rs1800012/TGFB1 rs1800471 polymorphisms protects against cervical insufficiency.