Research Links
When I first heard that there were Labrador Retrievers that were colours other than the common Black, Chocolate or Yellow, I was both surprised and excited. What I found when I started researching was that this is a very controversial topic and that the internet is FULL of information, supposed facts, experts’ opinions, etc. I weeded through everything I could find, on both "sides" of the issue, and came to my own conclusion: That the dilute gene is a naturally occurring recessive trait in the Labrador Retriever and that its existence in some Labradors does not imply that those dogs are not purebred Labrador Retrievers.
The links below are many of the popular sites that people will quote... on both sides of the issue. If you want to be educated on the topic and the viewpoints, this is a good place to start. As with anything found on the internet, just because it has been stated doesn't mean that it's factual.
I encourage you to formulate your own opinion, as I have done. Ultimately I turned to the science behind the colours, the history of the breed itself (including the dogs that went into the "making" of the Labrador Retriever breed) and the genetic testing available to us today. I found these far more helpful than speculation and rumors about how the first "silver" Labrador popped up.
I've also included some links on the history of Fox Red Labrador Retrievers as there are still "respected" breeders and those who think they know all about Labs that claim that they too are not purebred Labrador Retrievers! There are also links to other interesting/related information to the breed.
My research never ends. I'll continue to post helpful information as I find it!
"Domestication Syndrome"... an interesting look at how selecting for behavioral traits such as a more friendly nature can lead to marked physical changes in a species (such as coat color changes). http://www.genetics.org/content/197/3/795
St Johns, home of the St Johns Water Dog (ancestor of the Labrador Retriever) recently erected two statues to commemorate the Labrador Retriever & Newfoundland... the direct descendants of the St Johns Water Dog. https://nationalpurebreddogday.com/harbourside-parks-nod-to-two-historic-breeds/
A site that takes a very analytical look at the commonly propagated information out there regarding the silver Lab. An excellent examination... separating the rumors/myths that have spread exponentially from what is known as truth. http://silverlabs.blogspot.co.nz/
An interesting look into the St. John's Water Dog and its relationship to the current day Newfoundland and Labrador Retriever. Particularly interesting is an excerpt from an article written in 1876 regarding the St. John's Water Dog and its coloring -- black or brindle: http://retrieverman.net/tag/st-johns-dog/
A website focused on dispelling the myths by presenting research-based and reference-supported information about the dilute Labrador. Check out their blog section for several articles: http://www.truthaboutsilverlabs.com
A brief overview of the history of the Silver Lab, from a breeder's research: http://www.cimarronsilverlabs.com/History.html
An article by Mary Roslin Williams regarding the chocolate Labrador. From the March/April 1977 issue of The Labrador Retriever Magazine. Of particular interest is her reference to all the various dog breeds that were crossed into the Labrador Retriever in the early days... many of which carry the dilute gene: http://surrylabradors.blogspot.co.nz/2007/04/interesting-article-by-old-breeder.html
A speech made to the Labrador Retriever Club (LRC) in 1986 by Mary Roslin Williams, considered to be one of the greatest all-time breeders of the Labrador Retriever. She discusses the different breeds that were crossed into the Labrador Retriever in the early days to improve the breed: https://www.youtube.com/watch?v=kFlng4i8_R4
An easy to understand look at pigment in dog coat color: http://www.doggenetics.co.uk/pigment.html
A high level look at both sides of the controversial "silver" Lab issue by a Labrador trainer: www.labradortraininghq.com/labrador-breed-information/silver-labrador-retriever/
A typical article on the legitimacy of the "silver" Lab... focuses on the common concerns and is fairly one sided (against) them being purebred: http://www.thelabradorsite.com/silver-labradors/
A simple overview of the dilute colors... not really reference based and technically hearsay for the "support of dilutes" side but a decent starting point for someone just curious about dilute Labs: http://www.ellendalelabradors.com/SilverLabExplanation.html
Basic genetics regarding the colors of Labradors: http://www.doggenetics.co.uk/breeding.htm
Labrador mismarks: http://www.woodhavenlabs.com/mismarks.html
Information regarding Bolo pads: http://www.gundogtrainingforum.co.uk/phpbb/viewtopic.php?t=14013
Scientific article (abstract) regarding what the MLPH ("dilute") gene is and the effect it has on color: http://jhered.oxfordjournals.org/content/100/suppl_1/S75.short
The AKC's stance on silver Labs: http://silverlabs.blogspot.com/p/lrc-akc.html
How the first silver Labrador came to be. Crist Culo Kennels/Dean Crist interview: http://silverlabs.blogspot.com/p/culo-interview.html
A non-committal, easy read article regarding the silver Lab: http://www.labrador-retriever-guide.com/silverlabradorretrievers.html
Debunking the myths, lies and hype surrounding the controversial silver Labrador: http://silverlabs.blogspot.co.nz/p/silver-labrador-theses.html
History of the Fox Red Labrador: http://www.penara.com/foxred.html
The Labrador Retriever Club's stance. The argument for how a weimaraner must be part of the silver Labrador creation: http://www.woodhavenlabs.com/silverlabs.html
A breeder's anti-silver Labrador stance warning buyers beware. http://blueknightlabs.com/rare-silver-labradors/
The Labrador Retriever Club's stance on silver Labs. Discusses how genetically the Labrador does not have the "D" gene: https://thelabradorclub.com/news/
The origin of chocolate Labradors. Lots of old photos and ancestory: http://www.lakecharlesretrieverclub.com/2-Origin_of_Chocolate_Labrador_Retrievers.pdf
Why it's critical that good breeders market their dogs. (Original link was no longer valid but I found the article cut and pasted on this forum): http://www.dolforums.com.au/topic/250258-the-scandal-of-marketing-purebred-dogs/
The history of the Labrador Retriever including the St Johns Water Dog. Lots of photos: http://www.lorkenfarms.com/labrador%20Retriever%20history.htm
The details about Labrador Retriever genetics. Pour a big cup of coffee before tackling this one! http://www.labbies.com/genetics2.htm
History of the Fox Red Labrador Retriever. Lots of photos: http://www.ashdalekennels.co.nz/labradors/fox-red-labradors/
An overview of the dilute gene in general as well as a list of the MANY dog breeds that carry the dilute gene. Lots of photos: http://www.doggenetics.co.uk/dilutes.html
A laboratory's explanation of the various color genes and how they come into play. Some very helpful diagrams: http://www.vetgen.com/canine-coat-color.html
A scientific study showing how color dilution is related to the MLPH gene: http://www.biomedcentral.com/1471-2156/6/34
The dog breeds known to carry the dilute gene: http://www.doggenetics.co.uk/dilutes.html#breeds
A discussion about mismarks in Labrador Retrievers and the silver color: http://musingsofabiologistanddoglover.blogspot.co.nz/2011/12/mismark-case-study-labrador-retriever.html
The greying gene and how it is different from the dilute gene: http://www.doggenetics.co.uk/greying.html
The nitty gritty of coat color genetics. You better have passed Genetics 101 before you dive into this one! http://munster.sasktelwebsite.net/DogColor/dogcolorgenetics.html
An interesting page regarding Chesapeake Bay Retriever colouring (a very close relative to the Labrador Retriever): http://2browndawgs.com/2012/03/15/the-colors-of-chessies/
More about Chesapeake Bay Retriever colouring, in particular the ash (silver) colouring, and how long it has been part of the breed: https://amchessieclub.org/historical-notes-on-the-chesapeake/
English type, American type, Field type, Show/Bench type... a good article explaining the different Lab "styles" and proper terminology: http://www.woodhavenlabs.com/english-american.html