Combinations of 10 Cryptosporidium parvum oocysts, with various ratios of genotype I to genotype II, were isolated and subjected to PCR-restriction fragment length polymorphism analysis. Amplification of both genotypes in these samples ranged from 31 to 74% and yielded no information about the genotype proportions. In addition, since both genotypes were not always detected, amplification of a single genotype is not conclusive evidence that the sample contains only a single genotype.
Reed C, Sturbaum GD, Hoover PJ, Sterling CR. (2002). Cryptosporidium parvum mixed genotypes detected by PCR-restriction fragment length polymorphism analysis. Applied and environmental microbiology, 68(1)