Are COL1A1 gene polymorphisms associated with anterior cruciate ligament tear in the Indian population? Results of a preliminary case-control study

Introduction: Despite the identification of various intrinsic and extrinsic risk factors associated with ACL tear, the exact etiopathogenesis of ACL tear is still incompletely understood. The evidence for association of COL1A1 gene polymorphisms with ACL tear has been somewhat conflicting. Objective of the study is: to determine if rs1800012 and rs1107946 polymorphisms of COL1A1 gene are associated with ACL tear in an Indian population study group. Methods: Fifty clinically, radiologically and surgically-proven ACL deficient patients and 52 healthy controls were included in the study. After isolation of DNA from peripheral blood monocytes, real time PCR was carried out to genotype COL1A1 rs1800012 and rs1107946 polymorphisms. Results: Both the groups were matched for age and sex. Hardy Weinberg equilibrium was maintained for both genotypes. There was no signifi-cant difference in the genotype or allele distribution between the case and control groups for both rs1800012 (p=0.516) and rs1107946 polymorphisms (p=0.971 for GT and p=0.823 for TT) in this preliminary study. Conclusion: The rs1800012 polymorphism of COL1A1 gene remains the first and most extensively tested gene polymorphism for its association with ACL tear. Under-representation of the TT genotype has been observed in Swedish and South African Caucasian populations with ACL tear. This has not been noted in the Polish Caucasian population and in our study. More studies with larger study samples from different ethnic populations are needed before COL1A1 gene polymorphism screening tests are incorporated into ACL tear prevention programs. Level of evidence: III b (case-control study).