RARE VARIANTS IN MICRONESIANS 265 Micronesia (see below), we tabulated it with the polymorphisms. These three individuals were siblings; one parent was normal, the other was not tested. Rare Variants Four rare variants, affecting nine persons, were observed in a total of 8,520. determinations: (1) A fast albumin variant was detected by only one of the three screening systems in use for albumin, namely, the pH 5.0 sodium acetate buffer system of Weitkamp et al. [10] (see fig. 1). It occurred in a 5-year-old female K Fic. 1—Albumin variant starch gel patterns using the following buffer systems: 4: sodium acetate, pH 5.0; B: tris-EDTA-borate, pH 6.9. Albumin samples shown are normal serum 1, 5, 7, 8, and 11; Makiritare-2, 2; Marshall Island variant 3, 9; Makiritare-3, 4; Wapishana-1, 6, 12; Naskzpi 10. Normal samples include reference serum from our laboratory and serum from normal Marshall Island samples. All variants, except the presently reported Marshall Island variant, have been previously compared by Tanis et al. [2]. whose mother was normal (and not exposed to fallout), and whose alleged father was zlso normal, but there was paternity exclusion on the basis of the MN blood group antigens. This variant was first observed in 1974 and confirmed in a sample from the same individual collected in 1975. (2) An unusual lactate dehydrogenase pattern was observed in four, apparently unrelated, individuals. This pattern, shown in figure 24, is similar to the pattern seen in the LDH “Calcutta-1” variant re- ported by Ananthakrishnan et al. [12] and previously observed in the Western Caroline Islands by Blake et al. [13]. For three of these individuals neither parent was available. Both parents and two siblings of the fourth individual were normal; there was no parental exclusion with any of 12 polymorphic systems. The occurrence in this population of three other persons with the same defect strongly mili- tates against considering this a mutation. (3) A single individual was found to have a galactose-l-phosphate uridylyltransferase phenotype which was indistin- guishable trom the “Duarte” variant common in Caucasian populations [8]. Nei- ther parent of this individual was sampled. (4) The transferrin CB phenotype was observed in three unrelated individuals (fig. 2B). Although Hainline et al. [14]