title: Classification of Cryptosporidium species from patients with sporadic cryptosporidiosis by use of sequence-based multilocus analysis following mutation scanning.
abstract: In the present study, we analyzed genetic variation in Cryptosporidium species from humans (n = 62) with clinical cryptosporidiosis in South Australia. Sequence variation was assessed in regions within the small subunit of nuclear rRNA (p-SSU), the 70-kDa heat shock protein (p-hsp70), and the 60-kDa glycoprotein (p-gp60) genes by employing single-strand conformation polymorphism analysis and sequencing. Based on the analyses of p-SSU and p-hsp70, Cryptosporidium hominis (n = 38) and Cryptosporidium parvum (n = 24) were identified. The analysis of p-gp60 revealed eight distinct subgenotypes, classified as C. hominis IaA17R1 (n = 3), IbA9G3R2 (n = 14), IbA10G2R2 (n = 20), and IfA12G1R1 (n = 1), as well as C. parvum IIaA18G3R1 (n = 15), IIaA20G3R1 (n = 6), IIaA22G4R1 (n = 2), and IIcA5G3R2 (n = 1). Subgenotypes IaA17R1 and IIaA22G4R1 are new. Of the six other subgenotypes, IbA10G2R2, IIaA18G3R1, IIaA20G3R1, and IIcA5G3R2 were reported previously from the state of Victoria. This is the fourth record in Australia of C. parvum subgenotype IIaA18G3R1 from humans, which, to date, has been isolated only from cattle in other countries. This subgenotype might be a significant contributor to sporadic human cryptosporidiosis and may indicate a greater zoonotic contribution to the infection of humans in the area of study. Comparative analyses revealed, for the first time, the differences in the genetic makeup of Cryptosporidium populations between two relatively close, major metropolitan cities.
authors.affiliation: Department of Veterinary Science, The University of Melbourne, Werribee, Victoria 3030, Australia. ajex@unimelb.edu.au
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Jex
authors.forename: Aradhana
authors.initials: A
authors.lastname: Pangasa
authors.forename: Bronwyn E
authors.initials: BE
authors.lastname: Campbell
authors.forename: Margaret
authors.initials: M
authors.lastname: Whipp
authors.forename: Geoff
authors.initials: G
authors.lastname: Hogg
authors.forename: Martha I
authors.initials: MI
authors.lastname: Sinclair
authors.forename: Melita
authors.initials: M
authors.lastname: Stevens
authors.forename: Robin B
authors.initials: RB
authors.lastname: Gasser
mesh_terms: D000818:Animals; D001483:Base Sequence; D016000:Cluster Analysis; D003457:Cryptosporidiosis / Q000469:parasitology*; D003458:Cryptosporidium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics*; D005838:Genotype; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization / Q000379:methods; D011110:Polymorphism, Genetic; D015800:Protozoan Proteins / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013021:South Australia
chemical_list: D016054:DNA, Protozoan; D018840:HSP70 Heat-Shock Proteins; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; D012337:RNA, Ribosomal, 18S