Interaction makes the heart grow stronger

A novel interaction between GATA4 and TBX5 could explain phenotypic similarities (atrial septal defects) between patients with mutations in GATA4 or TBX5. The cardiac transcription factor GATA4 has not previously been implicated in a human disorder but a recent paper by Garg et al. provides evidence of mutations in GATA4 that cause atrial septal defects. Mutations in TBX5 have already been shown to cause similar atrial septal defects in Holt–Oram syndrome.