Figure 1. Gldc deficiency results in ventriculomegaly.

Unlike wild-type (A–E) and unaffected Gldc^GT1/GT1 (F–J) fetuses, a subset (7 of 13) of Gldc^GT1/GT1 fetuses (K–O) were affected by enlargement of the lateral (Lv) and third (III) ventricles at E18.5. The fourth ventricle (IV, arrow in E) does not differ in size between genotypes (compare D with E, I with J, and N with O), nor does the aqueduct (aq) at this posterior axial level. Choroid plexus is detected in lateral, third, and fourth ventricles (arrows in B) of all genotypes. However, the pineal gland (pg) and subcommissural organ (arrowheads in C and H) are absent in Gldc^GT1/GT1 fetuses displaying ventriculomegaly (M). (P–U) Following bilateral injection into the lateral ventricles of neonatal mice (P, Q, S, and T), dye distributed throughout the ventricular system including the fourth ventricle (IV) of Gldc^+/+ (R) but not Gldc^GT1/GT1 (U) mice. Scale bars: 1 mm (C, H, and M), 5 mm (P–U), and 0.5 mm (other panels).