TACSTD2 and gelatinous drop-like corneal dystrophy: Similarly, TACSTD2, which encodes the TROP2 protein, is the causative gene for human gelatinous drop-like corneal dystrophy (GDLD), which causes photophobia and vision loss due to amyloid deposition under the corneal epithelium (Tsujikawa et al., 1999; Takaoka et al., 2007).