SSU rDNA characterization of lymnaeid snails transmitting human fascioliasis in South and Central America.
J Parasitol
; 83(6): 1086-92, 1997 Dec.
Article
en En
| MEDLINE
| ID: mdl-9406784
ABSTRACT
The small subunit (18S) rRNA gene sequences of the lymnaeid morphs I and II (Mollusca Gastropoda Basommatophora Lymnaeidae) transmitting human fascioliasis in the high endemic zone of the northern Bolivian Altiplano and of Lymnaea cubensis from Mexico and Guadeloupe island (Caribbean) have been obtained by direct polymerase chain reaction PCR cycle sequencing and silver staining methods and compared to that of the 6 most common European Lymnaeidae species. Results allow us to establish definitively the distinction between the lymnaeids from the northern Bolivian Altiplano and L. cubensis. Lymnaea cubensis is a valid species distributed in North and Central America but absent in the northern Bolivian Altiplano. Lymnaeid morphs I and II from the northern Bolivian Altiplano both present the same 18S rDNA sequence, which is moreover identical to that of the European species Lymnaea truncatula. Significant nucleotide substitutions in helix E10-1 of the variable region V2 of the secondary structure suggest the need for distinguishing L. cubensis in the subgenus Lymnaea (Bakerilymnaea) with L. (B.) cubensis as type species. The subgenus Lymnaea (Fossaria) is retained, with L. (F.) truncatula as type species. The larger number of nucleotides in the 18S rDNA sequence of L. cubensis (1,860 bp) with regard to the other Lymnaea species (1,843-1,852 bp) is tentatively related to the more ancient paleogeographic origin of L. cubensis. The grouping of L. cubensis with L. truncatula and the relationship of Lymnaea auricularia with Lymnaea peregra in the phylogenetic trees obtained show an evolutionary parallelism with the digenean parasite species they transmit, namely Fasciola hepatica and Fasciola gigantica, respectively.
Buscar en Google
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ADN Ribosómico
/
ARN Ribosómico 18S
/
ARN de Helminto
/
ADN de Helmintos
/
Fascioliasis
/
Lymnaea
Límite:
Animals
País/Región como asunto:
America do sul
/
Bolivia
/
Caribe
/
Europa
/
Guadalupe
/
Mexico
Idioma:
En
Revista:
J Parasitol
Año:
1997
Tipo del documento:
Article
País de afiliación:
España