a–d, Immunofluorescence of human fovea cryosections double labelled with primary antibodies against ABCR and either green/red cone opsin or rhodopsin, and secondary antibodies conjugated to Alexi 488 (green) or Alexi 594 (red) dye and stained with DAPI (blue) nuclear dye. a,b, ABCR (Rim 3F4 monoclonal antibody8) and green/red cone opsin labelling, respectively. c,d, ABCR (Rim 5B4) and rhodopsin (Rho 1D4) labelling, respectively. os, Outer segments; onl, outer nuclear layer; inl, inner nuclear layer; gcl, ganglion cell layer; fp, foveal pit. Bar, 100 μm. e, Western blots of human peripheral (lane 1), foveal (lane 2) and macula (lane 3) extracts labelled for ABCR with Rim 3F4 (top), the rod cGMP-gated channel (rod CNG) with PMc1D1 (middle), and cone transducin (cone Tα) with the A1.1 antibody (bottom).