TCF4 and Fuchs endothelial corneal dystrophy: Visualization of the Iso-Seq unfiltered FLNC TCF4 CCS reads in the Integrative Genomics Viewer (IGV) revealed CAG (CAG in RNA, CTG in DNA) repeat lengths as long as 6 kb (2000 CAG repeats) in all three FECD patients (Figs 1 and 2, representative samples).