Table 2.
Results of gene flow simulations modeled after the historical recreation of the PWD breed and subsequent importation into the United States
| Original founders | Average generations to AA fixation | % Fixed AA | % Fixed aa | % Not fixed | Average “a” allele frequencya |
| 80 generations, bottleneck at 40 | |||||
| No selection | bb 70%b | 83.00 | 6.00 | 11.00 | 0.55 |
| 0.9 fitnessc | bb 70% | 86.00 | 1.00 | 13.00 | 0.25 |
| 0.5 fitness | bb 94% | 100.00 | 0.00 | 0.00 | 0.00 |
| 40 generations | |||||
| No selection | 13.00 | 70.00 | 1.00 | 29.00 | 0.47 |
| 0.9 fitness | 13.00 | 79.00 | 0.00 | 21.00 | 0.32 |
| 0.5 fitness | 12.00 | 98.00 | 0.00 | 2.00 | 0.29 |
| 40 generations, low-level migration | |||||
| No selection | n.d. | 23.00 | 0.00 | 77.00 | 0.16 |
| 0.9 fitness | n.d. | 28.00 | 0.00 | 72.00 | 0.16 |
| 0.5 fitness | n.d. | 46.00 | 0.00 | 54.00 | 0.06 |
| 40 generations, low-level migration, no “a” in founders | |||||
| No selection | n.d. | 26.00 | 0.00 | 74.00 | 0.13 |
| 0.9 fitness | n.d. | 40.00 | 0.00 | 60.00 | 0.14 |
| 0.5 fitness | n.d. | 52.00 | 0.00 | 48.00 | 0.07 |
| 40 generations, one hybridization event in first generation | |||||
| No selection | 13.00 | 73.00 | 1.00 | 26.00 | 0.28 |
| 0.9 fitness | 10.00 | 90.00 | 0.00 | 10.00 | 0.26 |
| 0.5 fitness | 10.00 | 95.00 | 0.00 | 5.00 | 0.13 |
a
Average calculated from only those simulations where neither allele was fixed. The average does not include all the simulations in which the frequency of “a” is 0 or 1.
b
Percentage of simulations in which the “A” allele was fixed in the population before the bottleneck (bb) occurred allowing no possibility of carrying the IC allele into the US population.
c
Fitness of the “aa” genotype relative to the “Aa” or “AA” genotype, where “a” is the allele responsible for IC.