Fig. 3. The triple PG1 knockdown phenotype is more severe than the double knockdowns. Morpholinos for each Hox PG1 gene were injected either in double (D: A1/B1 52%, n=25; E: B1/D1 48%, n=29; F: D1/A1 64%, n=33) or triple (C: A1/B1/D1 94%, n=35) combinations into the left-hand side of the embryo and Krox20 and Engrailed-2 (^*) expression analysed. The hindbrain region of early tailbud stage embryos is shown, with anterior to the top. Non-injected controls (NIC; A), and embryos injected on the left-hand side of the embryo with control morpholino (B) are also shown. Arrowheads indicate neural crest expression.