Research participants will be asked to undergo complete medical history, physical examination and blood tests. The purpose of these tests is to determine whether persons are predisposed to develop diabetes mellitus after kidney transplantation and also to make an early diagnosis if a patient develops diabetes mellitus. Medical information collected as part of the standard transplant evaluation and posttransplant medical care may be incorporated into this study. It is important to realize that research subjects will not be given an experimental drug as part of this study.