Fig. 3. Ocular abnormalities in adult Math5^-/- mice. (A,B) Ventral view of Math5^+/+ and Math5^-/- P21 brains, with rostral ends pointing upwards. Olfactory bulbs have been removed. Both optic nerves and the optic chiasm are absent in the Math5^-/- mouse. (C-F) Hematoxylin and Eosin-stained transverse sections of P21 Math5^+/+ (C) and Math5^-/- (D-F) eyes. Mutant retinae have regions of normal (D,F) and disrupted laminar structure (E and arrowheads in F). However, even in areas with largely normal structure, cells and axons are missing from the INL, IPL and GCL (D,E). Ectopic blood vessels are present in the vitreal space of mutant eyes (arrows in F). gcl, ganglion cell layer; inl, inner nuclear layer; onl, outer nuclear layer. Bars are 1.5 mm in A; 20 µm in C; and 200 µm in F.