Description of Echinococcus granulosus genotypes in human hydatidosis in a region of southern Chile.
BACKGROUND
Echinococcus granulosus species has a wide variety in both geography and hosts; indeed, 10 genotypes have been reported in studies on material of animal origin. The aim of this study was to genotype E. granulosus obtained from human hydatid cysts.


METHODS
The hydatid fluid and sand was collected from patients who underwent surgery for hepatic and pulmonary hydatidosis at Hospital Regional in Temuco, Chile, between 2004 and 2005. Two PCR systems were used: PCR Eg 9 and PCR Eg 16. The RsaI enzyme was used for RFLP. The genotype was confirmed using the sequence of one fragment of 366 bp from a mitochondrial gene (cox1).


RESULTS
The DNA of protoscolices from 24 samples was analyzed, 4 of them from pulmonary cysts and 20 from hepatic cysts. The 366 bp fragment was amplified in 20 out of 24 samples (83.3%). Enzymatic digestion revealed the presence of 3 possible genotypes: in 20 out of 21 samples (95,2%), a restriction was observed corresponding to the G1 or G7 genotypes; in the remaining sample genotype G4 or G7 was observed. Sequencing confirmed the presence of G1 genotype for 19 samples and G6 genotype for the remaining sample (G4 or G7 according to PCR-RFLP).


CONCLUSIONS
The PCR-RFLP technique enabled three possible genotypes present (G1 or G7, G4 or G7) to be established. Sequencing allowed us to decisively identify the G1 and G6 genotypes in our study group. Previous studies agree with the identification of the G1 genotype in our country. We consider it significant that the G6 genotype is present in Chile for its epidemiological implications.
Manterola
Carlos
C
Department of Surgery, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. cmantero@ufro.cl
Benavente
Felipe
F
Melo
Angélica
A
Vial
Manuel
M
Roa
Juan Carlos
JC
D000818:Animals; D001483:Base Sequence; D002677:Chile / Q000453:epidemiology; D051545:Cyclooxygenase 1 / Q000737:chemistry / Q000235:genetics; D018509:DNA, Helminth / Q000032:analysis / Q000302:isolation & purification; D004443:Echinococcosis / Q000453:epidemiology* / Q000469:parasitology*; D048209:Echinococcus granulosus / Q000145:classification* / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA
D018509:DNA, Helminth; D051545:Cyclooxygenase 1