In contrast, Zuo et al. studied resected medial rectus muscles in patients with concomitant exotropia and the amounts of fibronectin in the resected medial rectus muscle of patients with constant exotropia were significantly lower than those of the control and intermittent exotropic groups, while patients with intermittent exotropia did not show significantly lower amounts of fibronectin than those observed in the control group [13]. The gene discussed is FN1; the disease is Exotropia.