Extensive telomere shortening can cause mitotic catastrophe and subsequent cell death (Calado and Dumitriu, 2013; Shay, 2016), suggesting that the degeneration of MG in Tsc1fl/fl;Tyrp1-Cre mouse retina could be caused by telomere shortening beyond a critical length. This evidence concerns the gene TYRP1 and myasthenia gravis.