SLC5A1 and heart disorder: In contrast to SGLT2, which is not present in the heart, two other members of the SLC5A gene family, namely SGLT1 (SLC5A1) and the sodium-myoinositol cotransporter-1 (SMIT1, SLC5A3) are expressed in the heart and have been shown to contribute to Na+ influx in cardiac disease [33,34,103,104].