Subject Recruitment and Phenotyping
The study followed the tenets of the Declaration of Helsinki and was approved by Moorfields Eye Hospital (MEH) ethics committee (REC reference 09/H0724/25) and the Ethics committee of the GUH, Czech Republic. Written informed consent was received from all participants included in this study. A total of 450 individuals (185 males and 265 females; mean cohort age, 69 years) were recruited to the study. Participants either had clinical signs of FECD (numerous corneal guttae on slit-lamp biomicroscopy) or had corneal transplantation surgery (either penetrating or endothelial keratoplasty) for FECD. The cohort was stratified based on gender and ethnicity (Table 1). For control purposes, DNA samples collected from 550 white European individuals with AMD were used in the study (194 males and 356 females; mean cohort age, 78 years) (Table 1). All risk calculations presented were performed using the white European samples only (392 FECD samples and 550 AMD samples).
Table 1 Summary of CTG18.1 Genotyping Data in the FECD Cohort
N NE/NE E/NE E/E ≥1 E
Total FECD cohort (mean age = 69) 450 23.6% (106/450) 72.4% (326/450) 4.0% (18/450) 76.4% (344/450)
 Females (mean age = 70) 265 27.2% (72/265) 69.1% (183/265) 3.8% (10/265) 72.8% (193/265)
 Males (mean age = 68) 185 18.4% (34/185) 77.3% (143/185) 4.3% (8/185) 81.6% (151/185)
Subjects recruited at MEH 318 25.5% (81/318) 70.1% (223/318) 4.4% (14/318) 74.5% (237/318)
 White (82.4%) 260 22.7% (59/260) 71.9% (187/260) 5.4% (14/260) 77.3% (201/260)
 Other (17.6%) 58 37.9% (22/58) 62.1% (36/58) 0.0% (0/58) 62.1% (36/58)
Subjects recruited at GUH (white) 132 18.9% (25/132) 78.0% (103/132) 3.0% (4/132) 81.1% (107/132)
AMD cohort (mean age = 78) 550 95.8% (527/550) 4.2% (23/550) 0.0% (0/550) 4.2% (23/550)
 Females (mean age = 78) 356 96.1% (342/356) 3.9% (14/356) 0.0% (0/356) 3.9% (14/356)
 Males (mean age = 78) 194 95.4% (185/194) 4.6% (9/194) 0.0% (0/194) 4.6% (9/194)
Expanded alleles are defined as ≥50 CTG repeats. Abbreviations are as follows: NE, non-expanded CTG18.1 allele; E, expanded CTG18.1 allele; MEH, Moorfields Eye Hospital; GUH, General University Hospital in Prague.