Simulation results of mapping epistatic QTL in the F2 population
| Without epistasisa | With epistasisb | |||
|---|---|---|---|---|
| QA | QB | QA | QB | |
| Power | 1.000 | 0.238 | 1.000 | 0.500 |
| Position | 51.25 (7.73) | 89.63 (24.19) | 50.99 (7.95) | 90.46 (18.67) |
| 0.0125 (0.3701) | 0.0091 (0.3635) | |||
| a | 2.9941 (0.5696) | 1.8567 (0.4196) | 2.9658 (0.5700) | 1.3314 (0.6368) |
| d | 0.9816 (0.9018) | 1.0024 (0.8697) | ||
| iaa | 1.9897 (0.9948) | |||
| σ2 | 24.26 (3.29) | 24.02 (3.50) | ||
| h2 | 0.2158 (0.0445) | 0.2257 (0.0494) | ||
Numbers in parentheses are standard deviations. The critical values for claiming significance are χ21,0.05/20 = 9.14 and χ22,0.05/20 = 11.98. Two unlinked QTL, QA and QB, are simulated on the chromosomes with 11 15-cM equally spaced markers. QA is placed at 52 cM with additive effect 3 and dominance effect 1. QB is placed at 93 cM with additive effect 1 (a1 = 3, d1 = 1, a2 = 1; VA/VG = 76%, VB/VG = 16%). The mean is 0, and the additive-by-additive epistatic effect is 2 (μ = 0, iaa = 2; Vi/VG = 16%). The heritability is 0.2 (h2 = 0.2, σ2 = 25). Th sample size is 200 and the simulated replicates are 500.
↵a QTL mapping with epistasis ignored.
↵b QTL mapping with epistasis taken into account.