Fuchs endothelial corneal dystrophy (FECD) is caused by a corneal endothelial cell loss, leading to corneal edema and visual impairment. The most significant genetic risk factor for FECD is an expansion of the CTG18.1 locus in transcription factor 4 (TCF4). The current treatment for severe FECD is corneal transplantation, with Descemet stripping automated keratoplasty (DSAEK) as a common surgical method. Although successful in most cases, the risk for transplant failure due to diverse causes must be considered. In this study, we investigated if presence of TCF4 CTG18.1 expansion with more than 31 (n ≥ 31) repeats in donated corneal grafts could be a reason for corneal transplant failure after DSAEK. For this, nine consecutively failed DSAEK corneal grafts were genotyped for CTG18.1 repeat length. One-sided Mann–Whitney U test was performed to evaluate if failed DSAEK corneal grafts had longer CTG18.1 repeats than healthy controls from the same population. All failed corneal grafts had CTG18.1 n ≤ 27 with a median of 18 (IQR 8.0) repeats for the longest allele. There was no statistical difference in CTG18.1 repeat lengths between failed corneal grafts and the geographically matched healthy control group. In conclusion, none of the nine failed corneal grafts in our material had CTG18.1 repeat lengths ≥ 31, a cut-off known to have a biological relevance in FECD. Thus, our results suggest that the assessment of donors and inspection of the corneal tissue before the decision for procurement is sufficient, in terms of recognizing FECD in the donor.

Fuchs 角膜内皮营养不良 （FECD） 是由角膜内皮细胞丢失引起的，导致角膜水肿和视力障碍。FECD 最重要的遗传危险因素是转录因子 4 （TCF4） 中 CTG18.1 位点的扩增。目前严重 FECD 的治疗方法是角膜移植，后弹力层剥离自动角膜移植术 （DSAEK） 是一种常见的手术方法。尽管在大多数情况下成功，但必须考虑由于各种原因导致移植失败的风险。在这项研究中，我们调查了捐赠的角膜移植物中存在超过 31 （n ≥ 31） 重复的 TCF4 CTG18.1 扩增是否可能是 DSAEK 后角膜移植失败的原因。为此，对 9 个连续失败的 DSAEK 角膜移植物进行了 CTG18.1 重复长度的基因分型。进行单侧 Mann-Whitney U 检验，以评估失败的 DSAEK 角膜移植物是否比来自同一人群的健康对照具有更长的 CTG18.1 重复次数。所有失败的角膜移植物都有 CTG18.1 n ≤ 27，最长等位基因的中位数为 18 （IQR 8.0） 重复。失败的角膜移植物与地理匹配的健康对照组之间的 CTG18.1 重复长度没有统计学差异。总之，我们材料中 9 个失败的角膜移植物中没有一个具有 CTG18.1 重复长度≥ 31，这是已知在 FECD 中具有生物学相关性的临界值。因此，我们的结果表明，就识别供体中的 FECD 而言，在决定采购之前对供体的评估和对角膜组织的检查是足够的。