ORGAN XENOGRAFTING BETWEEN RODENTS - AN EVOLUTIONARY PERSPECTIVE

Rejection times of heart xenografts in several donor-recipient combina tions including the guinea pig, rat, hamster, and mouse are examined i n light of the paleontological history of rodents and the resulting ph ylogenetic distances between taxa. This multidisciplinary review at th e molecular, chromosomal and morphological levels suggests that xenogr aft rejection time is inversely proportional to the time divergence or phylogenetic distance, and that the binomial terminology concordant/d iscordant does not reflect the amplitude of phylogenetic distances.