To conduct a replication study to investigate whether the -945 CTGF genetic variant is associated with systemic sclerosis (SSc) susceptibility or specific SSc phenotype.
The study population comprised 1180 patients with SSc 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.
An independent association study showed in all the case-control cohorts no association of the CTGF -945 polymorphism with SSc susceptibility. These findings were confirmed by a meta-analysis giving a pooled OR = 1.12 (95% CI 0.99 to 1.25), p = 0.06. Investigation of the possible contribution of the -945 CTGF genetic variant to SSc phenotype showed that stratification according to SSc subtypes (limited or diffuse), selective autoantibodies (anti-topoisomerase I or anticentromere) or pulmonary involvement reached no statistically significant skewing.
The 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.