SP3 and heart disorder: The chosen examples include transcripts for transcription factors known to be involved in determining the sinus node pacemaking phenotype (Tbx1861), sinus node development (Mef2c62), cardiac development (Homez, Sp3, Gata163–65), cardiac development and adult function (Tbx2066), cardiac development and possibly the circadian clock (Nrd1d267,68) and cardiac disease (Atf6, Meox169,70).