Many people don't know or cannot tell the differences between merle and roan Am Cocker Spaniels. 
Hopefully, this page will give the reader enough information to decide what is what. 
And remember..please DO NOT list a dog you "think" may be merle.... 
as a roan. 

If in doubt..err on the safe side and try to register your dog as a merle. 
ASC is now looking at this matter and hopefully this problem will be resolved SOON.

The roan cocker goes back to when the english cockers and american cockers were basically one and the same.
In the 1940's when the American Cockers broke away from the English cockers, many Am cocker breeders
chose not to breed roans because it reminded them too much of the English cocker.
However, some breeders, specifically Philsworth Kennel continued to breed roan american cockers and your roans today go back to these lines.
Roan has always been a part of the American Cocker Spaniel.
And you can trace every TRUE roan back into the Philsworth lines and beyond.
 
 

COLORING: Can be tan pointed. Comes in all colors and varieties; black, brown, buff, red, sable, partis. 
 

PATTERN:It is an incomplete dominant dilution gene.
Generally the color will be a lighter shade 
than the actual color should be.
You may see a tiny spot or several areas
where the color is of the same shade but darker.
The over all appearance can show a marbling effect.Or it can have patches of different colors together.
The pattern is not spread evenly over the coat, but leaves patches of undiluted color scattered over the dog's body.  These areas can and often do include the nose, lips, and eyes. Sometimes they will have what they call a butterfly nose, which means the pigment in the nose is spotchy and leaves areas still pink, when the dog is older.
The color white will mask any merling, so be careful. Buff and sable can also mask merling.
 

Appearance At Birth: The merle gene DILUTES areas of color. 
A pup will appear as a lighter version of the color it would have been if not bred to a merle. 
There could be spots that are the actual darker color. For instance. 
A blue merle, is a diluted black dog. Instead of the entire coat being black,
the coat will be diluted to gray (blue). 
But you may see spots of black on the coat. Maybe just on the ears or the tip of a tail. ALWAYS look at the pups under good and bright light. 
If the dog is brown, the same thing applies. The coat will be a lighter brown, with the dark, normal color of brown patches.
If the dog is buff, it is very hard to tell, and looking at the dog in bright light is essential and go through the coat very carefully. Sometimes these are referred as cryptic or hidden merles. But true cryptic merle are generally rare.
Parti coats can be hard to tell too. Look for dilution and darker color of the same color. 
Sables can also be very hard to tell, with the merle pattern and the sable mixed together
Make sure you check ear tips, tails,nose,lips...everywhere for the merling.
The color white will mask any merling, so be careful.
 
 

Breeding: Merle is an incomplete DOMINANT gene
A merle will always produce at least 1 merle pup
no matter WHAT color it is bred to.
A DOUBLE merle will produce an entire
litter of merles, along with the possible lethal double merle gene. Pups that are not merle out of a merle breeding to a non merle cocker, do not have the lethal genes and are considered safe.
 

COLORING: Blue Roan, Brown Roan, Sable Roan , Orange Roan, Lemon Roan...and also can be tan pointed. Roans are considered partis.
 
 
 
 
 
 
 
 

PATTERN:The roan gene is expressed (seen)only in the white 
areas of spotted dogs. The roan has the base coat color interspersed with the white 
 
 

Appearance At Birth: They can look roan at birth, but generally look like a regular marked parti with  some smudging possibly on the muzzle or feet.
They appear to look like a  parti. (WHITE with perhaps some solid colored markings)But within a few weeks the roaning will become more and more apparant..The roan gene is expressed (seen)only in the white areas of spotted dogs. The roan has the base coat color interspersed with the white 
To see photos of the progression of ROAN from birth to1 year, in Am Cockers, click here.
As you can see, this does NOT look like merle. 

Thanks to Coreen for this photo
 

Often the paw pads in a baby roan pup will have a dark halo around them.
And you can see the "smudged" look on the chin and feet in this photo.

Breeding: Roan is a Simple DOMINANT gene.
You cannot get a roan unless one of it's parents are roan. It is NOT recessive.
It does not skip generations. Breeding roan to roan does NOT have any health issues associated with the gene.