Question for northern Italians

I am going to do my first ancestry dna kit (ever). I know on my dad's side his grandfather's family (my great-grandpa) immigrated from northern Italy (Turin). I also know that my great-grandfather's mom had jet black hair. (There were some old photos and his family would often talk about how she looked.) Now from what I have researched about northern Italians, they are genetically much different (and typically "lighter") than Italians farther south. (With northern Italians often having Celtic or Germanic mix of dna) My dad has black hair, pale skin and light eyes but in the summer he tans and gets very dark (almost brown) and does not burn. I also have dark hair (though not as dark as him), pale skin and the same eye color, and I too have the ability to get a very deep tan (if I choose to). I don't burn. Do you think there is something else that is part of the northern Italian dna that could explain this? (My mother is 100% Nordic and both her and my sibling are very fair, blonde and burn easily). I'm just curious how specific the breakdown may be for the Italian portion of my results... Any thoughts/opinions are welcome. Thanks for reading. x