Association of collagen type I alpha 1 gene polymorphism with inguinal hernia

A positive family history is an important risk factor for inguinal hernia development, suggesting a genetic trait for hernia disease. However, gene mutations responsible for abdominal wall hernia formation in humans have not yet been studied. We aimed to evaluate whether the functional Sp1 binding site polymorphism within intron 1 of the collagen type I, alpha 1 (COL1A1) gene was associated specifically with inguinal hernia disease.

85 participants with surgically diagnosed inguinal hernia disease, and 82 physically active controls without any history of connective tissue disease and hernia were recruited for this case-control genetic association study. Polymerase chain reaction and restriction fragment length polymorphism and agarose gel electrophoresis techniques were used to detect these polymorphisms.

Significantly, more patients gave a positive family history for an inguinal hernia compared to healthy controls (OR 3.646, 95 % CI 1.375-9.670, P = 0.006). COL1A1 Sp1 SNP (rs 1800012) was identified. Results demostrated statistically significant deviation from HWE for cases (P = 0.007), but not for the controls (P = 0.276). Our results revealed an increased frequency of COL1A1 Sp1 Ss genotype in inguinal hernia patients (OR 3.593, 95 % CI 1.867-6.915, P = 0.000).

This results suggest that polymorphism of the COL1A1 Sp1 binding site is associated with an increased risk for developing inguinal hernias. So, rs 1800012 locus is a potential candidate region for susceptibility in molecular mechanism of inguinal hernia pathophysiology.