Temporal distribution of the transferrin alleles (Tf aand Tf b) in Amazon Turtle (Podocnemis expansa Schweigger, 1812)

Teixeira AS; Moura AS; Oliveira PHG; Klein GN; Tancredi NS; Silva  CA

Teixeira AS Instituto Nacional de Pesquisas da Amazônia (INPA), Avenida André Araújo 2936, 69060-001, Manaus, AM, Brasil.
Moura AS Instituto Nacional de Pesquisas da Amazônia (INPA), Avenida André Araújo 2936, 69060-001, Manaus, AM, Brasil
Oliveira PHG Centro de Preservação e Pesquisas de Quelônios Aquáticos (CPPQA), BR 174, km101, AM 240, km 77, S/N, 69736-000, Presidente Figueiredo, AM, Brasil
Klein GN Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio), Reserva Biológica (Rebio) do Rio Trombetas, Praça da Feirinha, S/N, 68.275-000, Porto Trombetas, PA, Brasil
Tancredi NS Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA), Avenida Tapajós, 2267, Bairro do Laguinho, 68040-000, Santarém, PA, Brasil
Silva CA Instituto Nacional de Pesquisas da Amazônia (INPA), Avenida André Araújo 2936, 69060-001, Manaus, AM, Brasil

Keywords: Podocnemis expansa, Amazon Basin, transferrin allele frequencies, eletrophoresis, temporal analysis

Abstract

This study aims to evaluate the temporal distribution of allele frequencies at the codominant transferrin (Tf ) gene locus in three population samples of Amazon turtle (Podocnemis expansa) collected from the Rio Uatumã, Rio Trombetas and Rio Tapajós in the Amazon Basin, Brazil, over a period of 16 to 24 years ago. Confirming previous research, the Tf locus which was analyzed by starch gel electrophoresis showed a diallelic polymorphism with the presence of theoretically expected genotypes (Tf^aa, Tf^ab and Tf^bb), presumably encoded by the codominant alleles (Tf^a and Tf^b). A good genetic fit according to Hardy-Weinberg expectations within and among all the population samples was also noticed. Contingency tests on the overall transferrin allele distributions by calculating the chi-square (x²) showed no statistically significant temporal variation (x² = 3.05, d.f. = 5, 0.70 > P > 0.50) in the population samples of P. expansa in the surveyed areas

References

Alfinito J. 1975. A preservação da tartaruga amazônica. Brasil Florestal 7:49-53.

Alho CJR. 1985. Conservation and management strategies for commonly exploited Amazonian turtles. Biol Conserv., 32:291-298.

Alves RRN and Santana GG. 2008. Use and commercialization of Podocnemis expansa (Schweiger 1812) (Testudines: Podocnemididae) for medicinal purposes in two communities in North of Brazil. J Ethnobiol Ethnomed., 4:1-6.

Ayala FJ and Kiger Jr. JA. 1980. Modern Genetics. The Benjamins/Cummings Publishing Company, Inc., Menlo Park, California.

Bock BC, Páez VP and White MM. 2001. Genetic population structure of two threatened South American river turtle species, Podocnemis expansa and Podocnemis unifilis. Chelonian Conserv Bi., 4:47-52.

Chevolot M, Ellis JR, Rijnsdorp AD, Stam WT and Olsen JL. 2008. Temporal changes in allele frequencies but stable genetic diversity over the past 40 years in the Irish Sea population of thornback ray, Raja clavata. Heredity 101:120-126.

Frankham R, Ballou JD and Briscoe DA. 2002. Introduction to conservation genetics. Cambridge Univerity Press, Cambridge, UK.

Hartl DL. 2008. Princípios de genética de população. Third edition. Editora FUNPEC, Ribeirão Preto, SP.

Jacquemyn H, Honnay O, Van Looy K and Brine P. 2006. Spatiotemporal structure of genetic variation of a spreading plant metapopulation on dynamic riverbanks along the Meuse River. Heredity 96:471-478.

Jamieson A and Tuner RJ. 1978. The extended series of Tf alleles in Atlantic cod, Gadus morhua. In: Battaglia B., Beardmore J.A. (Eds). Marine Organisms: genetics ecology and evolution, NATO Conference Series IV: Marine Sciences, No. 2. Plenum Press, New York & London. 699-729.

Kambhampati S, Black IV WC, Rai KS and Sprenger D. 1990. Temporal variation in genetic structure of a colonising species: Aedes albopictus in the United States. Heredity 64:281-287.

Lucentini L, Palomba A, Gigliarelli L, Sgaravizzi G, Lancioni H, Lanfaloni L, Natali M and Panara F. 2009. Temporal changes and effective population size of an Italian isolated and supportive-breeding managed northern pike (Esox lucius) population. Fish Res., 96:139-147.

Pearse DE, Arndt AD, Valenzuela N, Miller BA, Cantarelli V and Sites Jr. JW. 2006. Estimating population structure under nonequilibrium conditions in a conservation context: continentwide population genetics of the giant Amazon river turtle, Podocnemis expansa (Chelonia: Podocnemididae). Mol Ecol., 15:985-1006.

Pritchard PCH and Trebbau P. 1984. The Turtles of Venezuela. Society for the study of Amphibians and Reptiles, Contributions in Herpetology 2. Fundación de Internados Rurales, Caracas, Venezuela.

Shikano T, Chiyokubo T and Taniguchi N. 2001. Temporal changes in allele frequency, genetic variation and inbreeding depression in small populations of the guppy, Poecilia reticulate. Heredity 86:153-160.

Sites Jr. JW, Fritzsimmons NN, Da Silva Jr. NJ and Cantarelli VH. 1999. Conservation genetics of the giant Amazon river turtle (Podocnemis expansa: Pelomedusidae) Inferences from two classes of molecular markers. Chelonian Conserv Bi., 3:454-463.

Teixeira AS, Jamieson A, Raposo JCP and Vieira AA. 1996. Transferrin polymorphism in Amazon Turtle (Podocnemis expansa) stocks. Braz J Genet., 19:559-564.

Vogt RC. 2008. Tartarugas da Amazônia. Gráfica Biblos, Lima, Peru.

Waples RS. 1989. A generalized approach for estimating effective population size from temporal changes in allele frequency. Genetics 121:379-391.

Williams CL, Blejwas K, Johnston JJ and Jaegert MM. 2003. Temporal genetic variation in a coyote (Canis latrans) population experiencing high turnover. J Mammal., 84:177-184.

Temporal distribution of the transferrin alleles (Tf aand Tf b) in Amazon Turtle (Podocnemis expansa Schweigger, 1812)

Abstract

References

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