Table 2. Periods of retinal Per1::luc or PER2::LUC rhythms in mice of different genotypes.
| Gene | Genotype | Period (h; Mean ± SEM) | P value | Statistical analysis | Sample number |
| Per1 | Per1+/+ | 24.10±0.17 (b) | Nonparametric Mann-Whitney U test | 10 | |
| Per1+/− | 23.27±0.06 (a) | P<0.001 | 12 | ||
| Per1−/− | Arrythmic | N/A | 12 | ||
| Per2 | Per2+/+ | 23.67±0.15 | One-way ANOVA withFisher’s LSD post hoctest | 13 | |
| Per2+/− | 23.28±0.14 | P>0.05 | 16 | ||
| Per2−/− | 23.19±0.30 | P>0.05 | 10 | ||
| Per3 | Per3+/+ | 24.40±0.19 (c) | NonparametricKruskal-Wallis testfollowed by Dunnett's T3 post hoc test | 12 | |
| Per3+/− | 23.00±0.02 (b) | P<0.001 | 10 | ||
| Per3−/− | 22.21±0.06 (a) | P<0.001 | 10 | ||
| Cry1 & Cry2 | Cry1+/+Cry2+/+ | 23.81±0.05 (c) | NonparametricKruskal-Wallis testfollowed by Dunnett'sT3 post hoc test | 10 | |
| Cry1+/−Cry2+/+ | 23.16±0.08 (b) | P<0.05 | 8 | ||
| Cry1−/−Cry2+/+ | 21.39±0.19 (a) | P<0.001 | 14 | ||
| Cry1+/+Cry2+/− | 24.59±0.10 (d) | P<0.05 | 10 | ||
| Cry1+/−Cry2+/− | 23.72±0.15 (bc) | P>0.05 | 13 | ||
| Cry1−/−Cry2+/− | Arrhythmic | N/A | 20 | ||
| Cry1+/+Cry2−/− | 25.25±0.30 (d) | P<0.05 | 12 | ||
| Cry1+/−Cry2−/− | 27.62±0.06 (e) | P<0.001 | 22 | ||
| Cry1−/−Cry2−/− | Arrythmic | N/A | 14 | ||
| Clock | Clock+/+ | 23.71±0.06 (a) | Independent samples t-test | 10 | |
| Clock+/− | 24.27±0.10 (b) | P<0.001 | 10 | ||
| Clock−/− | Arrythmic | N/A | 8 |
Letters indicate significant difference with a<b<c<d<e. P values are for comparisons to wild-type mice. A minimum of three animals were sampled for each genotype.