Originally posted by Kaji
It's not for medical reasons that they want to know. It's because, as stated in the first post, it is said to determine one's personality. From what I recall, A's are supposed to be the kind that are overly stressed out from being perfectionistic and driven, B's are supposed to be intellectual (I think, it's been a while), and O's can probably best be described by citing Eikichi Onizuka from GTO as an example.
Yeah, I realized that... guess I should have reworded to include medical reasons. Japan has some cute morning thing where these stupid animals climb up a vine and gives you your horoscope or whatever you want to call it of the day. As I don't know my horoscope, I couldn't play!