highly significantP = 0.015
Figure 3 shows that there were similar levels of NGF mRNA in the maxillary processes of erbB3 -/- and erbB3 +/+ embryos at E11, but by E12 there was a highly significant 18% reduction in the level of NGF mRNA in the maxillary processes of erbB3 -/- embryos compared with wild-type littermates ( P = 0.015, t -test, n = 34 embryos).