In more advanced stages of PVR (C2-D), 11 additional cytokines (CCL27, CXCL6, IL4, IL16, CXCL10, CCL8, CCL22, MIG/CXCL9, CCL15, CCL 23 and CXCL12) exhibited higher levels in the vitreous fluid compared to vitreous from eyes with pRD, but without PVR. The gene discussed is CCL8; the disease is X-linked retinal dysplasia.