We produced alloimmune sera against erythrocytes of the marsupial, Mon
odelphis domestica. By absorption fractionation, six operationally mon
ospecific blood typing reagents (hemolysins) were prepared. Using segr
egation analyses, we found that each reagent detects a blood group ant
igen controlled by an autosomal dominant gene. With the description of
these genetic markers, the utility of M. domestica as an animal model
is enhanced.