Distribution of blood groups among indians in South America. VI. In Paraguay

This paper on the distribution of hereditary factors in the blood of Indians in South America, reports the results of tests made on samples procured from Paraguayan Indians. Specimens from putatively full-blood persons were obtained from the following tribes: 88 Chamacoco, 36 Moro, 85 Chulupi, 207 Lengua, 100 Toba, 20 Yam Lengua, and 51 Guayaki, These 587 Samples were tested for factors in the A-B-O, M-N-S-s, P. Rh-Hr, Lutheran, Kell-Cellano, Lewis, Duffy, Kidd, and Diego systems. Serum samples were tested for haptoglobins and transferrins. He molysates, prepared from whole blood, were tested for hemoglobin types. The results are presented on appropriate tables as number and per cent of phenotypes for the various blood group antigens and their calculated allele frequencies. Locations of the populations from which blood samples were procured are listed on the tables and shown on a map (fig. 1). Of the 587 samples all except two Chamacoco belonged to group O. High frequencies are reported generally for M, s, P, R¹ (CDe), R² (cDE), k (100%) and Fy alleles in Paraguayn Indians. Low frequencies were generally reported for N, S, r (cde) and R° (cDe) alleles. There was a wide variation in frequencies for Di, Jk, and haptoglobin Hp¹. All tested for transferrins were classified as Tf C and all contained hemoglobin (A) as a major component. The following antigens were completely absent: Mi^a, Vw, p, P^k, r^y (CdE), K, and Le¹. Most notable is the unusual distribution of hereditary blood antigens among the Guayaki and Moro. The Guayaki had 100% P₁ and Fy^a; they were higher in R° (cDe), R¹ (CDe), and Jk^a; and lower in R² (cDE) and Hp¹ genes than other Indians; and Di was absent. The Guayaki differed from the other Indians also in having fair skin. The Moro were lower in the P¹ and Jk gene frequencies than is usually found in Amerinds, and the Di gene was absent. The Chamacoco also had an exceptionally low frequency for the P¹ gene (0.261).