T-distributed stochastic neighbor embedding (t-SNE)-dimension reduction of gene expression profiles of single cells prepared from WT mouse eyes. The populations of cells expressing Mfsd2a overlap with cells expressing markers of RPE (Rpe65, retinal pigment epithelium-specific 65 kDa protein), vascular endothelium cells (Tie1, tyrosine kinase with Ig-like and EGF-like domains 1), Müller cells (LIF, leukemia inhibitory factor), and astrocytes (Pdgfra, platelet derived growth factor receptor α).