Administration of TZDsmay, in patients with AMD, slow the progression to CNV, and in patients withdiabetic retinopathy attenuate the progress to PDR, provided that: (1) theirrisk of macular edema is low, (2) they lack symptoms of CHF or cardiomyopathy,and (3) are not taking insulin or nitrates. The gene discussed is INS; the disease is age-related macular degeneration.