Exploring the Genetic Role of Matrix Metalloproteinase-13 Variants in Pterygium Risk

Pterygium is a common ocular surface disorder characterized by abnormal fibrovascular growth and extracellular matrix remodeling, yet its precise molecular etiology remains unclear. Matrix metalloproteinases (MMPs) have been implicated in pterygium pathogenesis. However, the genetic contribution of MMP13 remains unexplored.

This case-control study evaluated the association between MMP13 promoter rs2252070 and intronic rs478927 with pterygium susceptibility, in a cohort comprising 160 patients and 320 age- and sex-matched controls by genotyping via polymerase chain reaction-restriction fragment length polymorphism methodology. The interaction between MMP13 genotype and age or sex were accessed by stratified analysis.

The genotypic distributions of MMP13 rs2252070 showed no significant differences between cases (AA: 33.1%, AG: 42.5%, GG: 24.4%) and controls (AA: 28.4%, AG: 45.6%, GG: 26.0%; p for trend=0.5720). Compared to the AA genotype, the odds ratios (ORs) for pterygium in association with AG and GG were 0.80 (95% CI=0.51-1.25, p=0.3829) and 0.81 (95% CI=0.48-1.34, p=0.4856), respectively. Under dominant and recessive models, no significant associations were observed (dominant: OR=0.80, 95% CI=0.53-1.21, p=0.3417; recessive: OR=0.92, 95% CI=0.59-1.43, p=0.7953). Similarly, rs478927 showed no significant genotypic or allelic associations with pterygium risk (all p>0.05). Stratified analyses indicated no effect modification by age or sex.

These findings suggest that MMP13 genetic variants rs2252070 and rs478927 do not significantly contribute to pterygium susceptibility. Given the known involvement of other MMPs, future studies should focus on alternative genetic markers to better understand pterygium pathogenesis and improve early detection strategies.