coat discoloration on dogs

Question
i have a boxer mixed with great Dane and he has started to have parts of his coat look like its drenched in water but it's been like this for a while

Answer
It's hard to say without seeing photos; "drenched with water" sounds to me like the fur is getting darker?  Pigment continues to migrate as the dog ages (for example, Dalmatian puppies are born white and develop spots over the next several weeks); some Danes have the merle gene, which causes spots or patches, but I'm not sure how pigment migration affects those - if this is a puppy, it could be just 'normal' development.  The other possibility that comes to mind is seasonal flank alopecia, though this is really more hair loss with the underlying skin turning black - but I'd imagine that during the transition it may just look like darker fur.  (If, instead, you mean sections of the coat are 'flatter' or thinner than others, then it could be a mite or endocrine issue.)

It's probably something the vet should check out, and a full thyroid panel isn't a bad idea (especially if this is an adult and not a puppy).

Good luck!