Figure 3.

Gonad histology of 21 dpf and 35 dpf wild-type and amh-mutant fish. (A–D) In histological sections, gonads in all eight 21 dpf wild-type sibling fish contained early oocytes (one gonad shown in each of two individuals in A and B). Gonads in six of eight 21 dpf amh^-26 mutants were morphologically like wild-type ovaries (C) and gonads of two of eight 21 dpf amh^-26 mutants were undifferentiated (D). At 35 dpf, wild-type fish contained gonads that were clearly either ovaries (4 of 8 fish) (E) or testis (4 of 8 fish) (F). In 35 dpf amh ⁻²⁶ mutants, most fish had ovaries (7 of 8 fish) (G) but one of eight fish had immature testis (H). Smaller boxed regions in several panels are magnified in the larger boxed regions at the right of these panels. Bar in E is 100 µm for all panels; Bar in the higher magnification boxes in A is 50 µm. WT, wild type.