Echocardiographic measurements (Fig. 1c) of female mice, surviving to 6–7 week pot-injection, revealed evidence of heart failure as characterized by severely reduced (P < 0.01) cardiac hemodynamic parameters in Tmem65 KD mice (Table 1; n = 6/group) with an 81% reduction in ejection fraction (14.83 ± 3.92% in Tmem65 KD mice; 76.75 ± 3.05% in control mice) and an 86% reduction in fraction shortening (5.33 ± 1.50% in Tmem65 KD mice; 39.10 ± 2.69% in control mice). Here, TMEM65 is linked to heart failure.