Have been an amateur genealogist for 15 years and have been able to find all 32 of my 3X great grandparents and about 50% of my 4X greats. Researching these genie lines has been very eye opening. My father's father's ancestors came from the south (Louisiana, Carolinas & Kentucky) and I found their slave holdings in various records. 

I wouldn't say I was "ashamed" when I found out this information. However, it did help me put many of my father's political views in perspective. The funny thing is, my father never had any direct knowledge of this until I showed him. But with my talks with him over he years, it was quite apparent that his father was very racist and I'm sad to say this influenced my father's views as well. 

If the racists, southern and northern, actually found out how much of their blood is part black, maybe there would be some greater hope for a greater understanding between the races. There are millions of whites walking around with black genes and they don't know it.