GFAP and macular telangiectasia type 2: This assumption also fits with the facts that Müller cells of the foveal walls and parafovea, but not cells of the Müller cell cone (which lies within the foveal avascular zone), have contact to blood vessels [13] and that the Müller cell markers vimentin and glutamine synthetase are reduced in the fovea of a macular telangiectasia type 2 patient compared to control tissues while the expression of glial fibrillary acidic protein (GFAP) is normal in the macular region [30, 31].