Fig. 5. Reduced viability and neurological abnormalities in Sox2^ß-geo/ENH mutants. (A) Survival of Sox2^ß-geo/ENH compound heterozygotes is decreased (n=50 embryos genotyped; n=510 adults genotyped). (B) Electroencephalography on Sox2^ß-geo/ENH (mut) and on wild-type (wt) control mice, performed in cortex (cx) and hippocampus (hip). Epileptic-like activity characterized by abnormal synchronized spikes is observed in mutant mice. These spikes appeared in clusters during the recording period and they were intermixed to basal activity similar to that observed in wild-type mice. (C,D) Effect of L-dopa and dopamine receptor agonists on circling and horizontal motility. (C) Decrease in the absolute number of turns (cumulative turns, mean±s.e.m.) and (D) decrease in cumulative horizontal counts (mean±s.e.m.), following administration of L-dopa (50 mg/kg, intraperitoneal injection), SKF 39383 (D1 receptor agonist, 56 mg/kg, subcutaneous) and quinpirole (QUINP; D2 receptor agonist, 3 mg/kg, subcutaneous). The number of turns and of counts were assessed for 30 minutes in wild-type (wt) and Sox2^{ß-geo/ENH(ko)} mutant mice. All drugs were given 10 minutes before the tests. A similar percentage decrease of turns was observed for each individual mouse after treatment, irrespective of the absolute basal number of turns. VEH, vehicle (saline). P<0.001 versus wild-type vehicle-treated group. P<0.05, P<0.01 and P<0.001 versus vehicle-treated mutant group, Tukey's multiple comparison test.