For those wondering  here  is a summary of how the tv series differs from the original comic book.    Just so you know, the comic is not entirely unPC it has its level of PC, it's just not that over the top, the asian-white pair does take place too.    Regarding the hand cut off scene, in the comic further into the plot Rick gets a hand chopped off, maybe they didn't want to have a disabled main character in the tv series, and they used the racist character as a way to keep that element (the chopped off hand)    The sniper head shot scratch also happens but to Andrea (the blond woman) in the comics she gets scratched in the face from a shot and sports a scar across her face, it seems they are using the racist brothers to get all the unsightly wounds the main characters get in the comic.    The same the whole stuck on traffic scene that leads to the girl getting lost in the woods doesn't happen (at least I don't remember), they do end up in the farm with Carl shot though...    And the people in the barn if I recall correctly, are the farmer family and friends that he didn't have the heart to kill and just in case there is some sort of cure...