Fig. 6. Intestinal characteristics displayed by the Hoxa5^–/– gastric mucosa. Alkaline phosphatase activity was tested on stomach sections from E18.5 wild-type (A) and Hoxa5^–/– (B,C) fetuses. In wild-type specimens, a faint enzymatic activity was present in the intestine and in the most distal part of the hindstomach (A, arrowheads). By contrast, in Hoxa5^–/– mutants, higher levels of reactivity that extended towards the forestomach were detected (B,C, arrows). d, duodenum. Scale bar: 100 µm.