Figure 3. Maternal formate supplementation prevents ventriculomegaly and hydrocephalus.

(A) Gldc^GT1/+ mice were mated and pregnant females were supplemented with formate from E0.5 to E15.5. (B) At E18.5, there was a significantly greater proportion of Gldc^GT1/GT1 fetuses that were unaffected (n = 8 of 10) in formate-treated litters than among Gldc^GT1/GT1 fetuses (n = 6 of 13) in control litters. *P < 0.05 by Fisher’s exact test. (C) Among offspring of formate-supplemented mice that were monitored at postnatal stages, none of the Gldc^GT1/GT1 mice (n = 0 of 35) developed hydrocephalus, whereas 30% (6 of 20) of nonsupplemented Gldc^GT1/GT1 offspring developed hydrocephalus by 6–7 weeks. **P < 0.002 by Fisher’s exact test. Number of litters: n = 19 supplemented and 35 nonsupplemented. (D–I) The ependymal lining of the third ventricle appeared intact in formate-treated fetuses at E18.5. Scale bars: 1 mm (D and G) and 100 μm (other panels).