Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil - Do the patterns of variation coincide?

A total of 2,708 individuals from the European-derived population of Rio Gr ande do Sul, divided into seven mesoregions, and of 226 individuals of simi lar origin from Santa Catarina were studied. Seventeen protein genetic syst ems, as well as grandparents' nationalities, individuals' surnames, and int erethnic admixture were investigated. The alleles which presented the highe st and lowest differences were GLO1*2 (16%) and PGD*A (2%), respectively, b ut in general no significant genetic differences were found among mesoregio ns. The values observed were generally those expected for individuals of Eu ropean descent, with the largest difference being a lower prevalence (34-39 %) of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. Th e Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Su[ was estimated to be as high as 11%. Based on the four dat a sets, the most general finding was a tendency for a northeast-southwest s eparation of the populations studied. Seven significant phenotype associati ons between systems were observed at the 5% level (three at the 0.1% level) . Of the latter, the two most interesting (since they were also observed in other studies) were MNSs/Duffy and Rh/ACP.