Effects of Speciation on Serum Proteins in the Genus Macaca with Special Reference to the Polymorphic State of Transferrin

Abstract

THE effects of speciation on the serum proteins of macaque monkeys and other primates are being studied in our laboratory by a combination of starch-gel electrophoretic and immunological techniques^1,2. In an initial survey of the sera from 19 cynomolgus monkeys (Macaca irus) and 17 rhesus monkeys (Macaca mulatta) we found that the cynomolgus sera contained a larger proportion of γ-globulin than the rhesus sera and also that all the cynomolgus sera showed only one transferrin whereas 10 of the 17 rhesus sera showed more than one transferrin. At the time, we observed that one of the ten rhesus sera showed three transferrin components and that in the other nine sera, each of which showed two components, the relative positions of the transferrins in starch-gel varied in some cases between the samples. In order further to define the polymorphic state of transferrin in the species Macaca mulatta and the apparent absence of this state in the species Macaca irus, the sera from 40 more rhesus monkeys, newly arrived from India, and from 40 more cynomolgus monkeys, newly arrived from the Philippines, were kindly provided for study by Parke, Davis and Co. The rhesus monkeys in this shipment were captured in an area the size of a township near the Nepal border. It was not possible to trace exactly where in the Philippines the cynomolgus monkeys were captured. We have now detected fourteen transferrin patterns in the rhesus monkeys and still only one pattern in the cynomolgus monkeys. Thirteen of the transferrin patterns were represented in the last shipment. Our work, then, not only independently confirms but also considerably extends the report by Blumberg³ of eight transferrin patterns in rhesus monkeys. Our results are particularly interesting in indicating that while the environment of one species selects for a polymorphic state, the environment of a closely related species selects against this state.