Tweed Dapple may also sometimes be called Patchwork
Dapple or Additional unidentified Dapple modifier?
(Tweed - Tw - can be shown as
MmTwTw,MmTwtw Genotype)
Very very occasionally some dapples have
additional colour patches to the standard 2 colour tones and this may be caused by
the Tweed gene which is a dapple modifier. This gene when carried by non dapple
dogs isn't visible so you have no way of knowing it's carried given it only
becomes visible on a dapple dog. Obviously you can figure out who carries it if
you are lucky enough to get a Tweed dapple in a litter - One parent Dapple with
no tweed gene showing the other a non dapple colour must be the Tweed gene
carrier! The Tweed gene makes the dapple pattern more than 2 colour tones, like
the chocolate dapple dog below - NOTE the addition of a fawn
colour tone giving in this case 3 colour tones over the standard
dapple 2 colour tones.
And to make the differences easier to see I've
digitally sampled the colours from the dog.
The gene can also work on a
silver dapple producing an additional medium silver/grey set of patch's to
the normal colour tones you would expect.
Normal dapples" are 2 toned (NO Tweed gene) or multi toned (with the Tweed
gene). Tweed gene is dominant to not Tweed dapple pattern and works only
with the Merle gene (Dapples).
Tweed creates one or more extra shades of eumelanin, not counting the
diluted (dappled) base and pheomelanistic points, if any. No currently known
health issues with this gene other than those that already apply to dapple
to dapple matings. Tweed is probably also know as Patchwork Dapple
particularly in the U.S.A. where there seem to more of them than in the UK
although in both countries they seem fairly rare. I must have looked at
thousands of dapples over the years and the one above is the only one I have
seen in the UK. If you know of more I would be really interested in hearing
about them and seeing pictures of them if at all possible. And if you can
add more information and or help amend/improve what I've written above I'd
really appreciate it as there seems to be very little accurate information
around.
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