A novel genotyping method for Cryptosporidium hominis

Exp Parasitol. 2021 Jun:225:108113. doi: 10.1016/j.exppara.2021.108113. Epub 2021 May 14.

Abstract

Cryptosporidiosis remains the leading protozoan induced cause of diarrhoea-associated mortality worldwide. Cryptosporidium hominis, the anthroponotically transmitted species within the Cryptosporidium genus, contributes significantly to the global burden of infection, accounting for the majority of clinical cases in many countries. This study applied high resolution melting analysis, a post-real-time PCR application, to the differentiation of six globally prevalent C. hominisgp60-subtypes. This novel method targeted three microsatellite, tandem repeat containing genetic markers, gp60, the genetic marker upon which current Cryptosporidium subtype nomenclature is based, MSB, and MSE, by which to differentiate between C. hominis isolates. This multi-locus approach successfully differentiated between all six C. hominisgp60-subtypes studied, some of which, such as IbA10G2, are known to exhibit global ubiquity. Thus, this method has the potential to be universally employed as a sensitive, cost effective and highly reproducible means to rapidly differentiate between C. hominisgp60-subtypes. Such a method would be of particular utility in epidemiological studies and outbreak scenarios, providing cost effective, clinically accessible alternative to DNA sequencing. The success of this preliminary study also supports further analysis of an expanded C. hominisgp60-subtype range and the potential expansion of the multi-locus panel in order to improve the discriminatory power of this approach.

Keywords: Cryptosporidium; Cryptosporidium hominis; High resolution melting curve analysis; Molecular genotyping; Real-time PCR; gp60.

MeSH terms

  • Cryptosporidiosis / parasitology
  • Cryptosporidium / classification
  • Cryptosporidium / genetics*
  • Cryptosporidium / isolation & purification
  • DNA, Protozoan / genetics
  • Feces / parasitology
  • Genetic Markers
  • Genotype
  • Humans
  • Multilocus Sequence Typing
  • Parasitology / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Sequence Analysis, DNA

Substances

  • DNA, Protozoan
  • Genetic Markers