Abstract:

Objective To evaluate the performance of microfluidic chips in the identification and genotyping of Malassezia species. Methods This study included 6 reference Malassezia strains and clinical Malassezia isolates from the scrapings of patients with pityriasis versicolor and follicular contents of patients with Malassezia folliculitis. These isolates were identified by DNA sequencing, random amplified polymorphic DNA （RAPD）-PCR and microfluidic chips. Cluster analysis was carried out and tree diagrams were generated. Results A total of 83 Malassezia isolates were obtained from 72 patients with pityriasis versicolor and 11 patients with Malassezia folliculitis. Genomic DNA of most strains was successfully amplified by PCR with two primers S22 and S24, and PCR with S22 primer produced more stable and clear amplification bands than that with S24. Positive bands of different sizes were repetitively obtained by using microfluidic chips, with interspecies and intraspecies polymorphisms observed in all the strains. On the basis of DNA sequencing, microfluidic chips and RAPD-PCR could be used to successfully distinguish the following eight species, i.e., M. furfur, M. sympodialis, M. globosa, M. pachydermatis, M. slooffiae, M. Japonica, M. yamatoensis and M. dermatis． Conclusions As a rapid, high-throughput and high-sensitivity method, microfluidic chips combined with RAPD-PCR shows an advantage for analyzing interspecies genetic diversity, genetic relationship of Malassezia species, as well as for identifying new Malassezia species.

Key words: Malassezia folliculitis