Mutant germ cells ectopically express meiotic markers SCP3 and STRA8. (A-F) ECAD and OCT4-EGFP (red) both label germ cells. (A) E16.5 129/SvJ Dnd1Ter/Ter germ cells that are morphologically wild-type express SCP3 (green), but ECAD-positive neoplasias (arrowhead) do not (B). At E17.5, in double mutants on a mixed genetic background, many, but not all, germ cells express SCP3 (C) and STRA8 (D), although they are never expressed in neoplasias (arrowheads). E17.5 C57BL/6J double-mutant germ cells also express SCP3 (E) and STRA8 (F). Scale bars: 50 μm.