one of my friends wants to find out what colour her girl carries,she has found out quite  bit from the pedigree but is about to send off for a dna test,do thry really work and if they do,what do they tell you,she has a choc and tan english cocker girl from choc/tan and black parents and further down there are several black and tan,chocs etc but she ants to find out if theres gold/red in there,would this test detemine this? I just want to make sure she isnt wasting her money.

I can't say whether this particular test is genuine or a rip off, but it should be possible to test for cocker coat genetics as they are known..

Red requires a pup to receive two red genes (ee) - red is recessive so a dog needs to have two or it won't be visible.  Gold requires the two recessive red genes AND two liver genes (bb) which are also recessive.

Recessive genes can hide and be passed on for generations because you need two copies for it to show, so even if she does get her dog tested she obviously needs to maximise her chances of it appearing in pups by picking a stud dog who red or gold.

I must say - big disclaimer - not a cocker person, mainly my colour genetics knowledge comes from snakes! (Where things are on the whole, a lot simpler as most colour genes are recessive!)

Colour gene tests have been available for Cockers for some time and yes, they are genuine tests and do determine whether a dog carries the gene for red\gold or orange if a particolour. Several labs offer the test but I'm guessing it's probably Laboklin your friend is looking at.

Red and gold are from the same gene. To produce a red/golden or orange roan puppy you need that puppy to inherit two copies of the recessive 'e' gene, one from each parent.  You don't need the two liver genes 'bb' to produce red just the 'ee'.  Your girl will have the two recessive "bb" genes as she's liver herself but they are not needed where red/golden are concerned.

Excellent Chriss, you have used the word "Liver" there are not enough people using this word these days, I have never bred a "chocolate" coloured puppy or used a "chocolate" coloured Stud dog, I will always register this colour as "Liver", yet people will breed from 2 Liver coloured dogs and call the colour Chocolate! This is a Labrador colour, the Cocker Spaniel colour is "Liver" .

I collected coat and dna samples for an American company who developed a coat colour test for all canines not just my breed, you start with 1 colour then add others if you need to, they will advise depending on breed and can offer a coat length test too.

Obviously the do health screening, parentage for pedigree as well as designer/mixed breed dogs.