Caste is normally understood to be a social term. But that is a common misunderstanding. Whenever talks or discussions involves cast, it normally termed as a social debate. But caste is more of a biological term personally to myself. Whenever a group of people is confined with a social barrier like caste unknowingly they confine themselves within a biological barrier. Whenever people of single caste marry within themselves they accidentally fall into a biological container that denies them from cross breeding. As for my personal opinion the core reason why a person should deny caste should not be for the sake of social logical problems but for the sake of biological disadvantages that he is going to phase.
Even though this subject has been talked quite a few times around the world for some time, it is rarely been taken into account. My personal concern is that the time that we are going to start realizing that caste has major biological issue rather than socio-psychological entanglement.