Figure 3.
Circadian period in founder strains and DO mice. The circadian period is shown in the founder strains (N = 49) and DO mice (N = 228). Vertical error bars represent the observed mean ± standard deviation. Among these mice with a measurable circadian period, we found significant differences across the founder strains (p = 1.52 × 10−8), with the CAST strain exhibiting the shortest period and several strains observed to have a period closer to 24 h. Among the DO mice, the average circadian period was 23.5 ± 0.4 h, with a range of 21.7 to 24.4 h. Thus, the circadian phenotype in the DO population fully covers and extends beyond the spread observed in the founders.