Unique genomic characteristics underlie the infectivity of divergent Cryptosporidium hominis subtypes to animals

The anthroponotic Cryptosporidium hominis differs from the zoonotic C. parvum in that it is not infectious to rodents. It has been found in nonhuman primates (NHPs) and equine animals. Here, we performed whole-genome sequencing of 17 animal-adapted C. hominis isolates. In a comparative analysis with 222 human isolates, the animal-adapted isolates showed significant genetic divergence, and genetic recombination shaped the population of NHP-adapted subtypes. In addition, these animal isolates had additional genes found in C. parvum and significant sequence differences in subtelomeric genes.