Fig. 1. Mutagenesis scheme. Males were mutagenized with ENU and crossed to wild-type females four weeks after the treatment. From each individual male
10±20 F1 offspring fish were used to establish F2 families by either crossing them to wild type fish or by F1 intercrosses. Mutations induced by the treatment are
eventually uncovered in the F3 generation after random intercrosses within the F2 families. F3 siblings of clutches with phenotypes segregating in a Mendelian
fashion were kept for the establishment of mutant lines.