We already have mutations, generally in women, for tetrachromaticism, who usually have male relatives with severe or moderate color blindness, in which the X chromosome encodes a different green cone. So they end up seeing red, strange-green, green, and blue, where strange-green is somewhere closer to red than green.

Only a few on record but they tend to have absolutely insane color matching and color perception. One of note worked in the fashion industry and could match fabrics perfectly even in varying lighting (e.g. working under fluorescent but able to match colors that would stay matched in halogen/stage lighting)

I have that already ;) it actually looks like muddy puke green than green. However, green stop lights look more “white” than green.

Some reds look like brown. I hate reds. I’m not sure about the Pantone-like color matching but I definitely see different colors than most people. To the point where my flight license is restricted.

Dichromatic but not trichromatic.