Fig. 6. (A) Position of axin1/mbl is at 62.8 cM on zebrafish LG 3 (59.7-83.2 cM) with respect to the position of marker z24851 that was used for genotyping. The LG 3 map was integrated from information available at http:/wwwmap.tuebingen.mpg.de and http:/zebrafish.mgh.harvard.edu/cgi_bin/ssr_map/view_lg.cgi. Left: scale in cM; right: scale in cR. (B) Point mutation A to T transversion in axin1 of mbl. (C) Wild-type uninjected embryo at ca 30 hpf and (D) embryo injected with 150 pg of mutant L399Q axin1 mRNA, which induced loss of telencephalon and laterally positioned eyes in 25% of 30 hpf embryos. (E,F) Whole-mount in situ hybridisation with axin1 riboprobe in 24 hpf embryos showing strong expression in the midbrain, ventral midhindbrain and ventral hindbrain, and a low signal in telencephalon, dorsal midbrain and midhindbrain boundary. The abnormal brain of mbl embryos (F) still shows expression of axin1 mRNA (arrows) comparable to that of the wild-type embryo (E).