AT least six different electrophoretic variants of human serum albumin have been found in man; three migrate more rapidly than normal and three less rapidly1,2. One of these, a rapidly migrating variant, occurs at a frequency of 5–30 per cent in several tribes of North American Indians3. As one aspect of a multidisciplinary study of the Yanomama Indians of southern Venezuela and adjacent parts of Brazil4, sera from 1,111 individuals residing in twenty-five villages were examined for albumin type. Although no example of the rapidly migrating variant which is common in North American Indians was observed, we did note, when testing 75 of 108 persons residing at the village of Borabuk (2° 45′ N. and 62° 05′ W.), four individuals who possess a variant which also migrates more rapidly towards the anode in starch gel electrophoresis than does normal albumin.