While rare, the literature describes several patients deficient for CD25 expression on their Tregs, with varying degrees of immune dysregulation [2,3,4,5,6]; a recent study highlights the ocular symptoms (itching, burning, foreign body sensation, photophobia) of a patient whose Tregs are deficient in the expression of CD25 [7]. The gene discussed is IL2RA; the disease is Photophobia.