ESR2 and heart disorder: Mutation of PBXIP1 in patients has not been associated with heart disease; however, mutation of the interacting transcription factor PBX1 has been linked to syndromic congenital heart defects.45 An interesting aspect of PBXIP1 is its interaction with and activation of ESR1 and ESR2, which represent potential mechanisms for sex-specific effects.42 Our data implicate PBXIP1 in cardiac growth, metabolism, and hypertrophy, but this needs to be further characterized under conditions of health and disease.