Since several P21 DEGs encode titin-associated proteins21, 22 (Figure 7d, network 'Ttn-associated'), we hypothesized similarity with diseases caused by Ttn mutations such as tibial muscular dystrophy (TMD).44, 45 Muscular dystrophy with myositis (mdm) mice (serving as a model of TMD) express a titin mutant lacking the N2A region, which binds Ankrd1, Ankrd2, and Ankrd23. The gene discussed is ANKRD23; the disease is tibial muscular dystrophy.