hi.. those two links posted by fenris don't work now, so sorry if i just repeat things mentioned in those articles..
if a canine had, for simplicity, just 4 pairs of chromosomes, then (without crossing chromosomes over) the wolf-genes-percentage distribution in F2 generation would look like this:
(left column: wolfblood percentage; right column: number of puppies out of 256, because there are 2^8 = 256 ways to combine 4 halves of chromosome pairs)
000.0% ... 1
012.5% ... 8
025.0% ... 28
037.5% ... 56
050.0% ... 70
062.5% ... 56
075.0% ... 28
087.5% ... 8
100.0% ... 1
000.0% |
012.5% ||||||||
025.0% ||||||||||||||||||||||||||||
037.5% |||||||||||||||||||||||||||||||||||||||||||||||||| ||||||
050.0% |||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||
062.5% |||||||||||||||||||||||||||||||||||||||||||||||||| ||||||
075.0% ||||||||||||||||||||||||||||
087.5% ||||||||
100.0% |
therefore there is just 27% chance (70/256) that an F2 puppy has exactly 50% wolfblood, but there is 71% chance (182/256) that an F2 puppy has between 37.5% and 62.5% wolfblood..
also, there is 64% chance (163/256) for "at least 50% wolfblood".. and 36% chance (93/256) for "at least 62.5% wolfblood", which equals to the chance for "at most 37.5% wolfblood"..
finally, there is still 0.4% chance that an F2 puppy is pure wolf and also 0.4% chance that an F2 puppy is pure dog.. and there is still chance for a today's real 25% x real 25% cross puppy to be a 50% half-wolf and then for 50% x 50% cross puppy to be a pure wolf..
so the dbase wolfblood value is just about the very peak of the probability..
charlie
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