Article

Host adaptation and host-parasite co-evolution in Cryptosporidium: implications for taxonomy and public health.

Division of Parasitic Diseases, Mail Stop F-12, Centers for Disease Control and Prevention, U.S. PHS/DHHS, 4770 Buford Highway, Atlanta, GA 30341, USA.
International Journal for Parasitology (impact factor: 3.39). 01/2003; 32(14):1773-85. DOI:10.1016/S0020-7519(02)00197-2 pp.1773-85
Source: PubMed

ABSTRACT To assess the genetic diversity and evolution of Cryptosporidium parasites, the partial ssrRNA, actin, and 70kDa heat shock protein (HSP70) genes of 15 new Cryptosporidium parasites were sequenced. Sequence data were analysed together with those previously obtained from other Cryptosporidium parasites (10 Cryptosporidium spp. and eight Cryptosporidium genotypes). Results of this multi-locus genetic characterisation indicate that host adaptation is a general phenomenon in the genus Cryptosporidium, because specific genotypes were usually associated with specific groups of animals. On the other hand, host-parasite co-evolution is also common in Cryptosporidium, as closely related hosts usually had related Cryptosporidium parasites. Results of phylogenetic analyses suggest that the Cryptosporidium parvum bovine genotype and Cryptosporidium meleagridis were originally parasites of rodents and mammals, respectively, but have subsequently expanded their host ranges to include humans. Understanding the evolution of Cryptosporidium species is important not only for clarification of the taxonomy of the parasites but also for assessment of the public health significance of Cryptosporidium parasites from animals.

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Keywords

10 Cryptosporidium spp
 
15 new Cryptosporidium parasites
 
70kDa heat shock protein
 
clarification
 
Cryptosporidium genotypes
 
Cryptosporidium meleagridis
 
Cryptosporidium parasites
 
Cryptosporidium parvum bovine genotype
 
Cryptosporidium species
 
general phenomenon
 
genetic diversity
 
genus Cryptosporidium
 
host adaptation
 
host ranges
 
host-parasite co-evolution
 
multi-locus genetic characterisation
 
partial ssrRNA
 
phylogenetic analyses
 
Sequence data
 
specific groups