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Enzyme polymorphism and genetic structure of Biomphalaria tenagophila (Gastropoda, Planorbidae) populations: founder effect

 

 

Douglas MascaraI; J.S. MorganteII

IDepartamento de Biologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina - UFSC, Caixa Postal 476, 88049 Florianópolis, SC, Brasil. Send correspondence to D.M.
IIDepartamento de Biologia, Instituto de Biociências, Universidade de São Paulo, Caixa Postal 11461, 1)5499 São Paulo, SP, Brasil

 

 

ABSTRACT

The genetic variation in 15 enzymatic loci was studied among nine populations of Biomphalaria tenagophila, the principal vectors of esquistossomiasis in the State of Sao Paulo. The polymorphism of the populations was manifested at seven of the 15 loci analyzed. Low heterozygosity values among populations was found (H = 0.00 to 0.086). The Sorocaba samples showed heterozygosity for the HBDH loci (H = 0.461), elevated in relation to the remaining populations. In the present study, it was possible to identify fixed alleles in B. tenagophila. The probable origin of distribution of the polymorphism in these populations is discussed and the hypothesis of a founder effect is proposed to explain colonization and genetic variability.

Keywords: Enzyme polymorphism; Biomphalaria tenagophila; Gastropoda; Founder effect.

 

 

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