Although glucocorticoids have proven useful in treating macular edema associated with RP, they have not shown effectiveness in reversal of rod functional loss in patients (49); however, it is possible that early treatment with glucocorticoids to activate TrkB, prior to evidence of rod functional loss, might prevent or delay mutant rod loss in RP. The gene discussed is NTRK2; the disease is retinitis pigmentosa 1.