Multilocus microsatellite typing of clinical Cryptococcus neoformans var.grubii strains from China and Brazil / 第三军医大学学报

ABSTRACT

Objective To understand the genotype distribution of clinical Cryptococcus neoformans var.grubii strains from China and Brazil using multilocus microsatellite typing(MLMT) method and to study the difference in their MLMT genotyping.Methods DNA was extracted from the identified 69 clinical Cryptococcus neoformans var.grubii strains.DNA fragments covering microsatellite loci(CNG1,CNG2,and CNG3) were amplified by PCR and sequenced.The number of each motif repeats in 3 microsatellite regions("TA","GA",and "CAT" repeats for CNG1,CNG2,and CNG3,respectively) was calculated.The MLMT types of 69 clinical Cryptococcus neoformans var.grubii strains were determined according to the repeat number of different motifs.Data were analyzed using SPSS 11.5 software.Results Five genotypes were identified in 33 clinical strains from China.Of these strains,29 were MLMT-17,accounting for 87.88% of the total strains.Ten genotypes were identified in 36 clinical strains from Brazil.Of the 36 strains,19 were MLMT-13,accounting for 52.78% of the total strains.Conclusion The difference is great in major genotype distributions of the clinical Cryptococcus neoformans var.grubii strains from China and Brazil.The genotype of clinical strains from Brazil is diversely distributed.