Abstract
Background
Rotator cuff disease (RCD) is the most common cause of shoulder pain and limitation of activities in sports and in repetitive work. The aetiology of RCD is not well established. A number of gene pathways are altered in RCD. Polymorphisms in Col1A1, Col5A1 (encoding collagen) and GDF5 (TGF-beta superfamily) can be associated with RCD susceptibility.
Materials and Methods
Single-nucleotide polymorphisms (SNPs) in Col1A1, GDF5 and Col5A1 were genotyped in a case-control study with 103 RCD patients and 104 controls in Caucasian and African populations who suffered from injuries in any other anatomical location. All patients provided signed informed consent. Sampling was carried out with a puncture of the pad of a finger using a sterile, single-use lancet. NSPs were determined by real-time polymerase chain reaction (PCR) using specific, unique probes with the analysis of the melting temperature of hybrids. The X2 test compared genotypes between groups. Multivariate logistic regression analysed the significance of many covariates and the incidence of RCD.
Results
We found significant differences in subjects who were exposed to heavy physical exertion involving the upper limbs (p=0.002). There was a significant difference in the distribution of the three polymorphisms in the GDF5 gene between the two races that were studied, with a higher frequency of TC heterozygotes in Caucasians and TT homozygotes in Africans (p=0.05). There were significant differences in the CC (rs143383) polymorphism in the GDF5 gene in patients with RCD (p<0.04).