[Jacob-list] gray spotted sheep

[Brenalan Farm]

I wrote to Karen off-list, but had some ideas for everyone to kick around. First off- I called Shannon in a panic last year because one of my lambs had a gray spot! The dam has a circle around her eye but doesn't appear to be a lilac. Curiously, the ram was from Bideawee, not a lilac, and he didn't throw any lilac lambs in 2 years here. Then I got a ewe over the summer from different lines that had a gray spot on her hind end. Both these sheep retain their gray spots after shearing and have black spots exposed to the same sunshine (or lack of it here in the northWET.) Anyway, it just seems to me that this has to be something related to the "blue" colors in dogs and cats. And that seems to be a "dilution" gene. What I read is that the gene affects dispersal of pigment in the fiber, and the clear areas are more reflective and create the blue/ lilac (in cats), and "gray". This is differentiated from "salt and pepper" gray that is actually black and white fibers intermixed. I plan to grab a sample from the spots over the wknd and see if my ancient microscope can see that sort of pattern. Anyway, this link explains that there are different genes for eumelanin (black, brown), a dilution gene, and a dilution modifier gene. If the sheep work like cats, and the genes work like this site suggests, the sheep with gray spots would have to have double recessives in both dilution and dilution modifier genes. If this is a new trend popping up (is it?), how do we all feel about it? Just in terms of color and landscaping, I think it is nice... but is it a sign that selective breeding is eliciting new traits?
http://www.messybeast.com/gene-symbols.htm   Scroll down to near the bottom... 

Brenda 
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