PITPNM1 and retinal degeneration: In principle, depletion of a gene product can suppress retinal degeneration in rdgB9 by one of the two mechanisms: (i) by altering the underlying biochemical abnormality resulting from loss of RDGB function, that is, the trigger; and (ii) by down-regulating downstream sub-cellular processes that are part of the degenerative process, that is, the effectors.