Among the F1 progeny produced by the artificial insemination of
eggs from 4 female recipients (female nos. 1, 5, 17, and 18; mentioned
in Section 2.2) and the milt from wild-type males,we found fry showing
an albino body color (see details in Okutsu et al., 2006a). If Y eggs had
been generated, the female to male ratio in the donor-derived F1 fish
group would have been 1:3 (XY × XY = 1XX + 2XY + 1YY, namely 1
female to 3 males; Fig. 1B). In the present study, we examined 16
randomly selected donor-derived F1 fish. Out of those 16 F1 fish, we
found 3 females and 13 males. The female:male ratio (3:13) was very
close to the theoretically expected one (4:12) if we assumed that Y
eggs had been produced.