Herein, we demonstrate a high senescence burden characterized by p19 and p21 abundance in SM/J discs as early as 4 weeks of age, and the NP and AF transcriptomic profiles during the 17-week degeneration process capture features in the established SenMayo gene set, suggesting that cell senescence is part of their degenerative process40. This evidence concerns the gene CDKN1A and atrial fibrillation.