On the other hand, PKM provided the best performance for the comparisons FTD vs. SCD (AUC 0.77) and FTD vs. MCI (AUC 0.80), for which UCHL1 and FABP3 showed lower diagnostic accuracy (AUC within the range 0.61–0.64). The gene discussed is PKM; the disease is Schnyder corneal dystrophy.