Table 4.

Clinical factors and gene loci associated with CCT.

Associated Factors	Clinical Significance	References
Graft Failure	CCT was associated with graft failure independent of the prediction made through ECD. The possibility of an unknown mechanism connecting CCT to graft failure has been posited.	[116,117]
Diabetes and Hyperglycemia	Associated with corneal endothelial dysfunction and resultant stromal hydration of the cornea. Osmotic fluid shifts and collagen cross-linkage are likely etiologies.	[118,119]
Endothelial Decompensation, Corneal Edema	Diseases involving endothelial dysfunction, such as Fuchs’ endothelial corneal dystrophy, progress into corneal edema. Resultant increase in CCT is a reliable method to measure disease progression.	[120,121,122]
ΔIOP > 25 mmHg (post-operation)	CCT was predictive of IOP increase 1 month postoperatively. Preoperative glaucoma was associated with early graft failure. CCT may represent the underlying physiologic link that connects glaucoma and graft failure.	[116,117]
GenesZNF469	Possible regulator of collagen synthesis and/or organization. Implicated in the development of Brittle Cornea syndrome, which exhibits markedly reduced CCT.	[123]
COL5A1	Encodes for the alpha-1 chain of type V collagen. Associated with a variation of Ehlers–Danlos syndrome, which also exhibits reduced CCT.	[124,125]
COL8A2	Encodes for the alpha-2 chain of type VIII collagen. Associated with posterior polymorphous corneal dystrophy and Fuchs’ endothelial corneal dystrophy, characterized by changes in the endothelial layer and Descemet’s membrane.	[124,125]
ZFP106	Contains an mHag loci which encodes for H-3a epitopes. These loci were previously shown to mediate corneal graft allograft rejection.	[126]

Abbreviation listed as followed. CCT: central corneal thickness; ECD: endothelial cell density; IOP: intraocular pressure; ZNF: zinc finger; ZFP: zinc finger protein; COL: collagen; mHag: minor histocompatibility antigen.