Objective: In this work we conducted a replication study to investigate whether the -945 CTGF genetic variant is associated with SSc susceptibility or specific SSc phenotype.
Methods: The study population comprised of 1180 SSc patients and 1784 healthy controls from seven independent case-control sets of European ancestry (Spanish, French, Dutch, German, British, Swedish and North American). The –945 CTGF genetic variant was genotyped using a Taqman 5′ allelic discrimination assay.
Results: First we conducted an independent association study that revealed in all case-control cohorts under study no association of the CTGF -945 polymorphism with SSc susceptibility. These findings were confirmed by a meta-analysis that reached a pooled OR of 1.12 (95 % CI 0.99-1.25, P=0.06). In addition, the possible contribution of the -945 CTGF genetic variant to SSc phenotype was investigated. However, stratification according to SSc subtypes (limited or diffuse), selective autoantibodies (antitopoisomerase I or anti-centromere) or pulmonary involvement reached no statistically significant skewing.
Conclusion: Our results do not confirm previous findings and suggest that the CTGF –945 promoter polymorphism does not play a major role in SSc susceptibility or clinical phenotype.