Expression of bmp2, 4 and 7 in dorsalized mutant embryos at 65-75% epiboly. Expression in wild-type embryos of bmp2b (A), bmp4 (B), and bmp7 (C). Expression of bmp2b, bmp4 and bmp7 in mutant embryos of snhty68a (D-F), sbndtc24 (G-I), swrta72/bmp 2b (JL) and snhsb1aub (M-O), respectively. In snhty68a mutants bmp2b (D) and bmp7 (F) expression are reduced in amount and to a more ventral domain. bmp4 expression is absent in snhty68a(E), sbn (H), swr (K) and snhsb1aub (N) on the ventral side, whereas the dorsal expression domain is unaffected. bmp2b expression is absent in the hypoblast ventrally, but is still present in the YSL and the dorsal margin in sbn/smad5 (G), swr/bmp2b (J) and snhsb1aub (M) mutant embryos. bmp7 expression is reduced in sbn/smad5 (I) and absent in swr/bmp2b mutant embryos, except for expression in the YSL and prechordal plate (L). In snhsb1aub mutants there is no detectable bmp7 expression, including the YSL and prechordal plate expression domains (O).