While our studies of continuous glial cell line-derived neurotropic factor (GDNF) treatment of one medial rectus muscle in infants resulted in both induction of strabismus as well as maintenance of strabismus after treatment was completed (McLoon L, et al. IOVS 2016;57:ARVO E-Abstract 1395), it remains to be determined whether these improvements to eye alignment after sustained IGF-1 treatment in adult strabismic monkeys would be maintained. The gene discussed is GDNF; the disease is Strabismus.