Fig. 1

On E13. TBX4-immunopositive cells were distributed in the epithelium of the hindgut and urorectal septum in normal group (a, b). No positive cells were seen in the hindgut or urorectal septum in ARM group (c, d). Red rectangles in a and c are shown at higher magnification in b and d. ×200 (a, c). ×400 (b, d). Black arrowheads: positive cells. CL Cloaca, H hindgut