In light of recent studies linking aberrant CDK5 expression and activity with epithelial mesenchymal transition and renal fibrosis [10, 11], we hypothesized that in SSc patients, cutaneous TGF-ß hyperactivity in SSc might be associated with augmented CDK5 expression and activity, contributing to development and persistence of skin fibrosis. The gene discussed is CDK5; the disease is renal fibrosis.