FGFR3 and microcephaly: The fgfr3 mutants were readily identified by their mandibular deformity with hyoid arch drooping toward the ventral side and mild domed-shaped skulls at 1 month (SL 10.0 mm) (Figure 3C), which resemble the microcephaly and high palate in the skulls of CATSHL patients 3, but the body length of WT and fgfr3 mutant had no significant change at 1 month (SL 10.0 mm).