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A Discussion of Coat Colour Genetics in the Lakeland Terrier Chapter 10— Untypical Colours By Ron Punter Brindle A distinction we need to make is that Brindle is not the same as Grizzle. In fact Brindle is completely untypical in a Lakeland. It is when black and yellow hair grows in bands or stripes all across the dog though it’s very variable and in some dark Staffordshire Bull Terriers they can appear almost black but close inspection reveals brindle. At one time it was suggested that brindle was part of the extension series and ascribed Eb but with the discovery of the K series Eb is long gone now and Brindle is known to be kbr it’s recessive to solid black but dominant to saddle pattern. A black Lakeland that carried the Brindle gene mated to a Saddle Pattern any of the pups that were not black would be brindle in the tan areas. According to what I have read it will not work in reverse and put yellow bands into black areas. If the yellow bands are narrower than the black it looks like it is yellow on black but genetically that’ s not the case - not easy to accept that a very dark Brindle Staffy is really a Red with black brindle on it rather than the reverse. Brindle is foreign to the Lakeland Terrier and not allowed by the standard. At the time of writing it is possible to do a commercial genetic test for the non brindle gene which is a bit of a backwards way of going about it and might not always be helpful. No doubt a test will be developed sooner or latter but apparently it’s more complicated than most genetic tests. B r i n d l e Great Dane Displaying Melanistic Mask (with black ears.) Indicating it’s: Ay- kbr- Em - Page 2 White - is simply lack of pigment –no pigment of any sort in the hair. White spotting genes blank out areas in the coat by stopping pigment production, in other words even an almost all white dog is not a white dog with (for example) black and tan patches but black and tan with very large white patches. This can be very counter intuitive - Dalmatians illustrate what selective breeding can achieve with a variable gene in there case arranging pigmented areas into “spots”. The very first standard of the Lakeland Terrier Association said “white predominent to disqualify” ( they misspelt predominant.) The KC standard used to say small tips of white on feet and chest “not to debar” but as we don’t have “barring” in the UK it was changed to “undesirable but permissible”. Most people would forgive “small tips” and probably it’s always been in the breed and due to what is know as residual white when the pigment doesn't quite migrate fully as the embryo develops. The picture elsewhere in this book of the Bedlington whelp with a white foot might be more obviously residual white. Especially if it was effecting rather a lot of just one leg and not following the usual progression of effecting more feet and chest first before spreading up the foot. Even a small amount of white in the usual distribution of toes—chest –tail tip might reasonably be assumed a random development fault but could actually indicate that the dog is carrying the sp (piebald) gene which is responsible for white in Fox Terriers. We would assume that a recessive gene of this type from a first cross to Fox Terrier will not produce white in a pup though it might as sp is partially dominant rather than completely recessive in Collies. In Boxers and some other breeds a single sp allele will produce a parti colour and a double dose an almost all white dog. These breeds where sp acts differently to a straightforward recessive must have other factors acting along with it (or it’s actually a different gene) but its an indication that the gene may tend to partial dominance so a considerable but relatively small amount of white might be due to the S sp coming into effect possibly not directly from the parents but carried forward from an earlier generation. With sp sp coming together in future generations from the cross breeding we would start to see Fox Terrier type makings which are extremely variable as will be clearly evident at any Fox Terrier show ring. Presumably anyone deliberately cross breeding to Wires would use a heavily marked one so we probably will never see anything like the amount of white as on the average Wire Fox Terrier coming out. Page 3 Irish Spotting si is a term being used for a pattern with rather less white than Piebald as might be seen in flashy Collies with bib and collar as well as white legs. As many Fox Terriers are heavily marked and not as white as desired, tending towards Irish spotting, then I think it best to consider it’s just a variation of Piebald. At the time of writing no gene for Irish spotting has been identified whilst a commercial test for piebald is available (though the test might not be reliable in all breeds) - DNA variant in Microphthalmia Associated Transcription Factor- (MITF) Parson Russells are bred for hardly any colour on the body at all just the head (some Fox Terriers are like this.) This pattern could also be considered a separate gene - Extreme White Piebald and designated sw. It’s noticeable that Parsons have a lot of Ticking which is a result of the s genes not completely clearing the coat of it’s underlying colour, this is sometimes speculated to be a separate gene T. Again no specific gene has yet been identified for sw or T. It would be possible to discuss more about selecting for white patterns but as its not wanted in Lakelands the only advice is to try to steer clear of it. If you do have white coming out genetic testing might help breed away from it . A puppy born with white patches on the head or torso shows almost certainly that both parents carry sp even if nether is displaying much white. In the 1940’s the then secretary of the LTC got the Club to engage solicitors to report Eddie Johnston to the KC for colouring the feet of Blackwell Minute Marvel. Eddie had the perfect defence, the white feet were visible on 1930’s Jimmy Overs Senior and Junior with pictures he had published.. Alice Graham Spence’s Egton Bridget, Foam, Crystal & Bachelor When it comes to a full white front like Egton Crystal’s really that can in no way can be considered acceptable nowadays. Remember even residual white on toes is “undesirable”. Page 4 .

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