Evidence of heterozygosity and recombinant alleles in single cysts of Giardia duodenalis
Giardia Duodenalis, micromanipulação, heterozigose, recombinação gênica, Cistos
Abstract Giardia duodenalis is divided into eight assemblages (named A to H). Isolates of assemblage A are divided into four sub-assemblages (AI, AII, AIII and AIV). While isolates of sub-assemblage AII are almost exclusively detected in human hosts, isolates of assemblage B are encountered in a multitude of animal hosts and humans. Here, we isolated single cysts of G. duodenalis from a human stool sample and found that one of them had overlaps of assemblage AII and B alleles and an unexpectedly high number of variants of the beta-giardin (Bg) and GLORF-C4 (OrfC4) alleles. In addition, one of the Bg alleles of that cyst had a fragment of sub-assemblage AII interspersed with fragments of assemblage B, thus indicating that this allele may be a recombinant between sequences A and B. Our results are unprecedented and put a check on the statement that different assemblages of G. duodenalis represent species with different host specificities.
Juliana Martins Aguiar, Sheila Oliveira Silva, Valdir Azevedo dos Santos, Sueli Akemi Taniwaki, Trícia Maria Ferreira de Sousa Oliveira, Helena Lage Ferreira, Lara Borges Keid, Fabio Gregori, Rodrigo Martins Soares
Revista Brasileira de Parasitologia Veterinária
Colégio Brasileiro de Parasitologia Veterinaria