Fig. 4. Developmental defects of Dnmt3L^mat–/– embryos from Dnmt3L^–/– mothers. (A) A wild-type E9.5 embryo, (B) a Dnmt3L^–/– littermate, and (C) Dnmt3L^mat–/– embryos. Most Dnmt3L^mat–/– embryos (left, 85%) show mild defects such as a smaller brain, incomplete closure of the rostral end of the neural tube (arrow), and smaller branchial arches. Some Dnmt3L^mat–/– embryos (right, 15%) display severe developmental defects, including an open neural tube in the midbrain region (arrow), smaller forebrain, and incomplete turning.