Interest and limitations of Spliced Leader Intergenic Region sequences for analyzing Trypanosoma cruzi I phylogenetic diversity in the Argentinean Chaco.
Internal and geographical clustering within Trypanosoma cruzi I (TcI) has been recently revealed by using Multilocus Microsatellite Typing and sequencing of the Spliced-Leader Intergenic Region (SL-IR). In the present work, 14 isolates and 11 laboratory-cloned stocks obtained from a geographically restricted area in Chaco Province, Argentina, were analyzed by PCR and sequencing of SL-IR. We were able to differentiate 8 different genotypes that clustered into 4 groups. One of these groups was classified within the formerly described haplotype A and another one within the recently described SL-IR group E. Both were phylogenetically well-supported. In contrast, none of the stocks from the Chaco province were grouped within the cluster previously named haplotype D despite the fact that they shared a similar microsatellite motif in the SL-IR. No evidence of recombination or gene conversion within these stocks was found. On the other hand, multiple ambiguous alignments in the microsatellite region of SL-IR, affecting the tree topology and relationships among groups were detected. Finally, since there are multiple copies of the SL-IR, and they are arranged in tandem, we discuss how molecular processes affecting this kind of sequences could mislead phylogenetic inference.
Unidad de Epidemiología Molecular (UEM), Instituto de Patología Experimental, Universidad Nacional de Salta-CONICET, Av. Bolivia 5150, CP4400, Salta, Argentina. nicotomasini@yahoo.com.ar
Nicolás
N
Tomasini
Juan J
JJ
Lauthier
María M
MM
Monje Rumi
Paula G
PG
Ragone
Anahí A
AA
Alberti D'Amato
Cecilia
C
Pérez Brandan
Carolina I
CI
Cura
Alejandro G
AG
Schijman
Christian
C
Barnabé
Michel
M
Tibayrenc
Miguel A
MA
Basombrío
Alejandra
A
Falla
Claudia
C
Herrera
Felipe
F
Guhl
Patricio
P
Diosque
D001118:Argentina; D001499:Bayes Theorem; D014355:Chagas Disease / Q000469:parasitology / Q000635:transmission; D021901:DNA, Intergenic / Q000235:genetics*; D016054:DNA, Protozoan / Q000235:genetics; D014644:Genetic Variation; D005838:Genotype; D005843:Geography; D006239:Haplotypes; D006801:Humans; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing / Q000379:methods*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D020038:RNA, Spliced Leader; D017422:Sequence Analysis, DNA; D014349:Trypanosoma cruzi / Q000145:classification* / Q000235:genetics*
D021901:DNA, Intergenic; D016054:DNA, Protozoan; D020038:RNA, Spliced Leader