D-14N Free Communication/Poster Genetics
Although it is well established that there is a high incidence of chronic Achilles tendon injuries as a result of participation in physical activity, the exact mechanisms that cause these conditions are poorly understood. Some studies, however, have suggested that some individuals have a genetic predisposition to this condition.
The aim of this study therefore was to determine whether the alpha 1 type V collagen (COL5A1) gene, which encodes for a minor structural protein found in tendons, is implicated in the pathogenesis of chronic Achilles tendinopathy.
Fifty-three Caucasian subjects diagnosed with chronic Achilles tendinopathy (AT) using clinical criteria and 115 non-injured Caucasian control subjects (CON) were genotyped for the BstUI restriction fragment length polymorphism (RLFPs) within the COL5A1 gene.
There was a significant difference in the allele frequencies (A1, A2 and A3) of the BstUI RLFP within the COL5A1 gene between the injured and non-injured subjects (Pearson X2=15.3, p = 0.0005). The frequencies of the A1 (AT 78.3% vs CON 67.0%) and A3 (AT 5.7% vs CON 0.8%) alleles were higher in the AT group than in the CON group, while the frequency of the A2 allele was higher in the CON group than in the AT group (AT 16.0% vs CON 32.2%). Therefore, individuals with an A2 allele are less likely of developing chronic Achilles tendinopathy (odds ratio of 2.5; 95% CI 1.4 – 4.5).
The BstUI RFLP within the COL5A1 gene is associated with chronic Achilles tendinopathy and that the A2 allele of this gene appears to have a protective role.