title: Genotyping and phylogenetic analysis of Giardia duodenalis isolates from Turkish children.
abstract: BACKGROUND
  Giardiasis is caused by the intestinal protozoan parasite Giardia duodenalis (synonyms: G. lamblia, G. intestinalis), which is one of the most frequent parasites that infect Turkish children. However, molecular characterization of G. duodenalis in Turkey is relatively scarce. The present work aimed at genotyping G. duodenalis isolates from Turkey using molecular techniques.
  
  
  METHODS
  In the present study, 145 fecal samples from children were collected to search for the presence of Giardia by microscopy and PCR screening. PCR generated a 384 bp fragment for β-giardin. The PCR products were sequenced and the sequences were subjected to phylogenetic analysis by using PHYLIP.
  
  
  RESULTS
  Based on the phylogenetic analysis of the sequences, assemblage A, B, and mixed subtypes were determined. Of 22 isolates, 11 were identified as assemblage A (50%), 7 were assemblage B (31.8%), and 4 were assemblage AB (18.2%). Association between G. duodenalis assemblages and the epidemiological data was analyzed. No correlation was found between symptoms and infection with specific assemblages (P>0.05), but we found statistically significant association between age and the assemblage AB (P=0.001).
  
  
  CONCLUSIONS
  The association between G. duodenalis and the epidemiologic data were analyzed. Since assemblage A is the more prevalent subgroup compared with assemblage B, this subgroup might be responsible for common Giardia infections in Turkey. This is the first study that included a detailed phylogenetic analysis of Giardia strains from Turkey.
authors.affiliation: Department of Medical Microbiology, Kocaeli University, Umuttepe Campus, Kocaeli, Turkey.
authors.forename: Gulden Sonmez
authors.initials: GS
authors.lastname: Tamer
authors.affiliation: Department of Medical Biology, Kocaeli University, Umuttepe Campus, Kocaeli, Kocaeli, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Kasap
authors.affiliation: Department of Medical Microbiology, Institute of Health Sciences, Kocaeli University, Umuttepe Campus, Kocaeli, Turkey.
authors.forename: Doganhan Kadir
authors.initials: DK
authors.lastname: Er
mesh_terms: D000704:Analysis of Variance; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D005243:Feces / Q000469:parasitology; D005838:Genotype; D016829:Giardia lamblia / Q000145:classification / Q000235:genetics*; D005873:Giardiasis / Q000453:epidemiology* / Q000469:parasitology*; D006801:Humans; D007223:Infant; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014421:Turkey / Q000453:epidemiology
chemical_list: D017931:DNA Primers; D015800:Protozoan Proteins