COL5A1 and systemic sclerosis: The relative gene expression of the cutaneous fibroblasts showed a significant increase in COL5A1 and COL5A2 for the SSc skin compared to the healthy controls (2.07 ± 0.31 vs. 0.54 ± 0.10, p = 0.01 and 1.40 ± 0.15 vs. 0.19 ± 0.03; p = 0.002, respectively) (Figure 3A).