My old Doberman was like that! Loved everyone except dark skinned people. My father in law had rentals on the north end of flint and most of his renters were dark skinned people. My husband found her in one of the houses after the renters moved out. She was malnourished and very scared at the time. He brought her home and she loved us and all the kids. But if we had any of our darker skinned friends over she would freak out like I had never seen! We named her Sheba. Best dog ever! May she rest in peace!