Blood groups of Cakchiquel Indians from Sumpango, Guatemala

ABO, MN, Rh, P, Lutheran, Kell, Duffy and Kidd blood group systems were studied in a sample of 135 Cakchiquel‐speaking Indians from Sumpango, Dpto. Sacatepequez, Guatemala. Sumpango represents an almost exclusively endogamous isolate in the western highlands some 42 km outside of Guatemala City. The bloods were collected by families, and tests on them are much more revealing than on unrelated individuals because the genotypes are so often evident, and genes that could not have been otherwise detected are revealed. What is lost in numbers of unrelated people is probably more than compensated for by the precision of gene identification. Some evidence of foreign genes in this Indian sample is afforded by gene B in a mother and three of her children, in a small frequency (0.01) of R −2,−3 ( cde or cDe ), and perhaps in gene MU or Mu in a mother and son. Gene frequencies for the Sumpango sample are very similar to those of Matson and Swanson's ('63) Cakchiquel from nearby Chimaltenango and Patzicia. The Sumpango sample shows lower P and Jk a and higher R 2,−3 ( CDe ), and of these the low P and high R 2,−3 stand outside of the known Maya range.