The CpA135 gene as a marker to identify Cryptosporidium species infecting humans.
Of the 22 species currently recognized as valid in the Cryptosporidium genus, C. parvum and C. hominis account for most cases of human infections worldwide. However, C. meleagridis, C. canis, C. felis, C. suis, C. muris, as well as the cervine, rabbit and monkey Cryptosporidium genotypes, have also been recognized as the etiologic cause of both sporadic and epidemic cryptosporidiosis in humans. Molecular methods are necessary to distinguish species and genotypes of Cryptosporidium, due to the lack of reliable morphological variations. The aim of this work was to determine the genetic polymorphisms in a fragment of the A135 gene in isolates of C. parvum, C. hominis, C. meleagridis, C. canis, C. muris, C. andersoni and the Cryptosporidium cervine genotype. Primers were designed on conserved regions identified on a multiple alignment of the C. parvum, C. hominis and C. muris sequences, the three species for which information is available at the genome level. PCR amplification and direct sequencing of a 576 bp fragment revealed the presence of numerous single nucleotide polymorphisms (SNPs) among the species/genotype tested. The genetic variability was exploited to design a PCR-RFLP assay useful for a rapid identification of the most important human pathogens in the genus Cryptosporidium.
Tosini
Fabio
F
Department of Infectious, Parasitic and Immunomediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy. fabio.tosini@iss.it
Drumo
Rosanna
R
Elwin
Kristin
K
Chalmers
Rachel M
RM
Pozio
Edoardo
E
Cacciò
Simone M
SM
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D003457:Cryptosporidiosis / Q000175:diagnosis* / Q000469:parasitology; D003458:Cryptosporidium / Q000145:classification* / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics*; D012680:Sensitivity and Specificity; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013045:Species Specificity
C514023:Cpa135 protein, Cryptosporidium parvum; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins