Genetic Maternal Ancestry and Surname Heritage in Rio Grande do Sul, Brazil.

REITCHERT, LM; HUNEMEIER, T.; RAMALLO V; CERQUEIRA, SC; BISSO-MACHADO, R; BORTOLINI MC; GUNSKI, J

Foz de Iguaçu, PR

Congreso; 58° Congresso Brasileiro de Genética; 2012

Sociedade Brasileira de Genética

Due to its matrilineal heritage, the mitochondrial DNA (mtDNA) has been used in populational studies, allowing toevaluate admixture processes. Mitochondrial lineages are grouped in haplogroups, and these can have a determinedgeographical origin. Surnames are other regulated heritage system, and this way they can also be useful markers tocharacterize the genetic structure of populations. This work aims to identify the mitochondrial haplogroups in aRio Grande do Sul state (Brazil), relating them to surnames, to verify the contribution of Europeans, Amerindians,and Africans in the formation of this population. Each individual answered a short genealogical survey, along with ablood sample. The sample consisted of 147 individuals, which had their mtDNA sequenced (HVS-I: position from16,024 to 16,569, and HVS-II: 001 to 576, the portion located immediately at 5’ of the control region was alsosequenced). The frequency of European, Amerindian, and African haplogroups were, respectively 0.740, 0.170, 0.090.According to databases from Instituto de Imigração e Colonização da Polícia Marítima, Arquivo Histórico Nacional, andInstituto Histórico e Geográfico Brasileiro, each surname was assigned to a certain populational or geographic origin.Rio Grande do Sul state showed a greater frequency of european haplogroups (0.740) compared to other researcheson the Brazilian population as a whole (0.390, n = 247; Alves-Silva et al. 2000; Am J Hum Genet 67:444-461) andalso greater than showed in earlier studies in this one state (0.370, n = 150; Marrero et al. 2007; Hum Hered 64:160-171; 0.480, n = 31; Marrero et al. 2005; Am J Hum Biol 17:496-506). The frequency observed for the surnameswere 0.600 of Iberic origin, 0.200 are Italian, and 0.130 of German origin, and in a lower frequency surnameswhich could not have their origin determined. These values are close to frequencies found by Dornelles et al. 1999(Genet Mol Biol 22:151-161) in samples of Rio Grande do Sul and Santa Catarina states. The elevated frequency ofEuropean mitochondrial ancestrality could have origin in the state’s great colonization processes, as the governmentpolitics’ incentivized the migration of couples and complete familiar groups. But a complex process of admixturesince the earlier times of the “conquest” also happened. This admixture was characterized by an assimetry, whichinvolved majoritarilly European men (“colonizers”) and Native women. African lineages present in the samples are aheritage of the population brought to America enslaved, which received European surnames in their arrival in Brazil.Financial Support: FAPERGS, CAPES, CNPq