To accomplish the main objective, we decided to quantify total GAG concentration in the blood, which reflects tissue alterations of PGs/GAGs, and to assess quantitatively MMP-3 and MMP-10 and their tissue inhibitors, i.e., TIMP-1 and TIMP-2, as well as TGF-β in the plasma of patients with systemic sclerosis, when compared to healthy individuals. The gene discussed is MMP10; the disease is systemic sclerosis.