Analysis of the varieties,genotypes and mating types of 110 clinical cryptococcal isolates from China / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the molecular epidemiology of clinical cryptococcal isolates from China by analyzing the constituents and distributions of the varieties,genotypes and mating types (MAT)of them.Methods (1)PCR fingerprinting and PCR amplification were performed by using the minisatellite-specific core sequence of wild-type phage M13 as single primer.Genotypes of the 110 cryptococcal isolates from China were assigned by comparison with the reference strains of the 8 major molecular types loaded on gel.(2)Identification of the varieties and mating types was carried out by PCR using the specific primers of the varieties and mating types.Results Of the 110 clinical cryptococcal isolates,strains of Cryptococcus neoformans var.grubii with genetype VNⅠ and mating type MATα were the most representative ones(89.1%)followed by strains of C.neoformans var.gattii(8.2%)including isolates of genotype VG I,mating type MATα(7.3%)and genotype VGⅡ,mating type MATα(0.9%);AD hybrids with the genotype VNⅢ,mating type MAT-/α and genotype VN Ⅲ,mating type MATα/-(1.8%);and isolate of C.neoformans var.neoformans with the genotype VNⅣ and mating type MATa(0.9%).Conclusion Of the clinical isolates from China,all three varieties and AD hybrids are found.The vast majority(>99%) of strains possess the α allele in MAT locus and most of them are C.neoformans vat.grubii with the genotype VN I,which accord with the data of most studies of clinical molecular epidemiology in other geographic areas.However.no genotype of VNⅡ.VGⅢ and VGⅣ isolates are found in this study.