well... I haven't been very active with the breed like I was... but...
Cockers are interesting because they're broken up into the three color categories. Black, ASCOB (Any Solid Color Other than Black) and Parti.
Black Variety-Solid color black to include black with tan points. The black should be jet; shadings of brown or liver in the coat are not desirable. A small amount of white on the chest and/or throat is allowed; white in any other location shall disqualify.
ASCOB -ranging from lightest cream to darkest red, including brown and brown with tan points. The color shall be of a uniform shade, but lighter color of the feathering is permissible. A small amount of white on the chest and/or throat is allowed; white in any other location shall disqualify.
Parti-Color Variety -Two or more solid, well broken colors, one of which must be white; black and white, red and white (the red may range from lightest cream to darkest red), brown and white, and roans, to include any such color combination with tan points. It is preferable that the tan markings be located in the same pattern as for the tan points in the Black and ASCOB varieties. Roans are classified as parti-colors and may be of any of the usual roaning patterns. Primary color which is ninety percent (90%) or more shall disqualify.
Tan Points--The color of the tan may be from the lightest cream to the darkest red and is restricted to ten percent (10%) or less of the color of the specimen; tan markings in excess of that amount shall disqualify. In the case of tan points in the Black or ASCOB variety, the markings shall be located as follows:
1) A clear tan spot over each eye;
2) On the sides of the muzzle and on the cheeks;
3) On the underside of the ears;
4) On all feet and/or legs;
5) Under the tail;
6) On the chest, optional; presence or absence shall not be penalized.
Tan markings which are not readily visible or which amount only to traces, shall be penalized. Tan on the muzzle which extends upward, over and joins shall also be penalized. The absence of tan markings in the Black or ASCOB variety in any of the specified locations in any otherwise tan-pointed dog shall disqualify.
Roan colors in American Cockers are:
Blue Roan-Which is basicly a black and white parti where the individual black hairs intermingles
with white which often gives a bluish appearance.
Brown Roan, Chocolate Roan or Liver Roan-Brown and white parti with brown hairs intermingled in the white
Orange Roan..sometimes called Red Roan & Strawberry Roan-Which is a red and white parti with red hairs intermingled in the white
All 3 can also have tan points, although you generally won't really see the tan points in a red roan
There are NO health issues associated with the roan gene.
I've seen sable and merle cockers, but they're not an acceptable show color and very controverisial depending on who you're talking to in the breed.