P797: A likely pathogenic variant of PBX1: Abnormal renal morphology and multiple cardiac anomalies identified by fetal ultrasound

The Pre-B cell leukemia homeobox 1 (PBX1) gene on chromosome 1 encodes a transcription factor belonging to a family of proteins that interact with Hox proteins to regulate cellular proliferation and differentiation. PBX1 is constitutively expressed in many tissues throughout the body, including the bladder, kidneys, heart and brain. During embryonic development, it is crucial in various pathophysiological processes in osteogenesis, renal morphogenesis and morphologic mapping. Several PBX1 variants have been recently reported to be associated with CAKUTHED syndrome, characterized by kidney and urinary tract syndrome with or without hearing loss, abnormal ears, or developmental delay.