Fig. 6. Early cardiac markers are normal in hst mutant embryos at the 15-somite stage. Dual in situ hybridization using: (A) nkx2.5/ntl, (B) hand2/ntl, (C) bmp4/ntl, (D) cmcl2/ntl, (E) vhmc/ntl, (F) ntl alone. The ntl probe indicates the anterior extent of the notochord (arrow in F) (Serbedzija et al., 1998).