philippe: thanx for that link..
dharkwolf: but that (rather simple) math WAS about recombining chromosome pairs (though it was written as ch.s and half-ch.s, where ch.s were taken for ch. pairs) - but what it was without was crossing chromosomes over, which is not that often, just like mutations.. or do you mean cross-overs by that "can and will recombine"? am i wrong with its rareness?
the real distribution curve IS much more narrow (as you said; 45-55% wb is at 70% chance, 40-60% wb is at 95% chance, 35-65% wb is at 99% chance) because, in fact, canines have 39 chromosome pairs instead of just 4 used in my simplified example.. and more, i was talking solely about an F2 generation - in next generations things get more and more complicated..
anyway, my aim was to show probabilistic nature of the wolfblood value.. sharper is the peak, the less useless is the wolfblood value.. but i was definitely not talking about qualities of a "resulting" puppy.. there is an obvious difference among 25% wb canines, when different 25% of genes are wolfish..
and the second thing was, that the chance of 25% x 25% summing to 50% is not that small.. i was curious about its "exact" level, so to back it with some math again, here is how 25% F2 x 25% F2 will come out as an F3: (of course, this is not valid, or exact, for any other FX than F2 x F2, as there is probability distribution uniformity broken in later generations)
for a 25% wolfblood F2 canine, there are 24 different genotypes.. (with 4 ch. pairs)
forming pairs of two such canines makes:
2% of pairs that give: 25% wolfblood puppies at 100% chance (i.e. always)
24.5% of pairs that give: 12.5% wb at 25% ch, 25.0% wb at 50% ch, 37.5% wb at 25% ch;
73.5% of pairs that give: 00.0% wb at 6.25% ch, 12.5% wb at 25.0% ch, 25.0% wb at 37.5% ch, 37.5% wb at 25.0% ch, 50.0% wb at 6.25% ch;
this all gives (for, say, 196 puppies):
00.0% ... 9 ... (4.59%)
12.5% ... 48 ... (24.49%)
25.0% ... 82 ... (41.83%)
37.5% ... 48 ... (24.49%)
50.0% ... 9 ... (4.59%)
00.0% |||||||||
12.5% ||||||||||||||||||||||||||||||||||||||||||||||||
25.0% |||||||||||||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||
37.5% ||||||||||||||||||||||||||||||||||||||||||||||||
50.0% |||||||||
almost 4.6% chance for 25% F2 x 25% F2 summing to 50% F3! ..or am i wrong again?
charlie
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