COL1A1, COL4A3, TIMP2 and TGFB1 polymorphisms in cervical insufficiency.

OBJECTIVES

To investigate the association between selected single nucleotide polymorphisms (SNPs) with cervical insufficiency and its relationship with obstetric history.

METHODS

Twenty-eight women with cervical insufficiency (case group) and 29 non-pregnant women (control group) were included. The SNPs sequenced included rs2586490 in collagen type I alpha 1 chain (COL1A1), rs1882435 in collagen type IV alpha 3 chain (COL4A3), rs2277698 in metallopeptidase inhibitor 2 (TIMP2), and rs1800468 in transforming growth factor beta 1 (TGFB1).

RESULTS

We found a higher frequency of the normal allele in the control group (65.5%) and the homozygous mutated genotype in the case group (64.3%) for rs2586490 in COL1A1 (p=0.023). An unplanned finding in the cervical insufficiency group was a higher gestational age of delivery (median≥38 weeks) in the mutated allele than in the wild-type genotype (median of 28.2 weeks) for rs2857396, which is also in the COL1A1 gene (p=0.011).

CONCLUSIONS

The findings of the present study corroborate the hypothesis that cervical insufficiency has a genetic component and probably involves genes encoding proteins in the extracellular matrix, in addition to inflammatory processes.