In a comprehensive review of the circulating cytokines and chemokines in sarcoidosis patients, which included a comparison between fibrotic (n=19) and nonfibrotic (n=21) sarcoidosis, IL-7 was one of three cytokines (the other two were IL-5 and GM-CSF) that were significantly different between the fibrotic and controls but not between fibrotic and nonfibrotic sarcoidosis [74]. The gene discussed is IL7; the disease is sarcoidosis.