Moreover, it was also recently shown that Tbx20 (a member of the Tbx1 subfamily of T-box genes which is required for cardiomyocyte proliferation during heart development) (48) can act as transcriptional repressor of Mes1 leading to increased proliferation of cardiomyocytes and preservation of cardiac function following MI in adult mice (49), thus confirming the key role of Meis1 in regulating cardiomyocyte proliferation and its promising potential as therapeutic target for cardiac regeneration post-MI. The gene discussed is TBX1; the disease is myocardial infarction.