So close, so far away: analysis of surnames in a town of twins (Cândido Godói, Brazil)

ZAGONEL DE OLIVEIRA, M; SCHULER-FACCINI, L; DEMARCHI, DA; ALFARO, EL; DIPIERRI, JE; VERONEZ, MR; COLLING CASSEL, M; TAGLIANI RIBEIRO, A; SILVEIRA MATTE, U; RAMALLO, V.

ANNALS OF HUMAN GENETICS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 77 p. 125 - 136

0003-4800

Candido Godoi is a small Brazilian town known for high rates of twin birth. In 2011, a genetic study showed that this localized high rate of twin births could be explained by a genetic founder effect. Here we used isonymic analysis and surname distribution to identify population subgroups within 5316 inhabitants and 665 different surnames. Four clusters were constructed based on different twin rates (P 0.001; MRPP test). Fishers alpha and consanguinity index showed low and high values, respectively, corresponding with observed values in isolated communities with high levels of genetic drift. Values of A and B estimators confirmed population isolation. Three boundaries were identified with Monmonier´s maximum difference algorithm (P = 0.007). Inside the isolated sections, surnames of different geographicorigins, language, and religion were represented. With an adequate statistical methodology, surname analyses provided a close approximation of historic and socioeconomic background at the moment of colony settlement. In this context, the maintenance of social and cultural practices had strong implications for the populations structure leading to drift processes in this small town, supporting the previous genetic study.