SMC3 and Anxiety: In the light/dark transition test (Takao and Miyakawa, 2006), whereas the distance traveled, time spent in the light box, and number of transitions did not differ between Smc3+/+ and Smc3+/− mice (Fig. 5, A–C), the latency of Smc3+/− mice to cross into the light box was significantly greater (Fig. 5 D), which suggests enhanced anxiety in Smc3+/− mice.