Furthermore, FAT1 is located in the vicinity of the FSHD-associated D4Z4 array on 4q35, and its expression is down-regulated in fetal and adult muscles of FSHD1 and FSHD2 patients [14, 119], suggesting that traditional FSHD-causing contexts may not only enhance DUX4 expression but also lead to lowered FAT1 expression in affected muscles. Here, DUX4 is linked to Facioscapulohumeral dystrophy.