It is hypothesized that the cytoplasm and nucleus can be reciprocated because they have nuclear localization signals and nuclear export signals.24 In humans, the aberrant expression of Fxr1 in skeletal muscle has been shown to cause facioscapulohumeral muscular dystrophy.25 In this study, the Fxr1 expression was reduced in the kidneys of SHR and SHRSP rats and was expressed in tubular cytoplasm of mesodermal origin, which is the same as that of skeletal muscle, and may be involved in the proliferation and growth of tubular cells. This evidence concerns the gene FXR1 and facioscapulohumeral muscular dystrophy.