Keywords
Amazon Basin
transferrin allele frequencies
eletrophoresis
temporal analysis
How to Cite
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 (Tfaa, Tfab and Tfbb), presumably encoded by the codominant alleles (Tfa and Tfb). 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
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