Abstract: Objective: Cryptococcus neoformans var. grubii isolates from 6 different cities in our country using multilocus microsatellite typing (MLMT) method were genotyped to explore the genotypic distribution of the variety. Methods: The DNA of forty-three isolates of Cryptococcus neoformans var. grubii which have been identified was extracted. The DNA fragments covering microsatellite loci CNG1, CNG2 and CNG3 were amplified using PCR, and then were sequenced. The numbers of each motif repeat in 3 microsatellite regions ("TA" repeats for CNG1, "GA" repeats for CNG2, and "CAT" repeats for CNG3) were calculated. According to the repeat numbers of these motif , the MLMT types of 43 strains of Cryptococcus neoformans var. grubii were determined. Results：Out of 43 isolates，the percentage of MLMT-17 was 83.72%. In the clinical and environmental isolates, the percentages of MLMT-17 were 86.67% and 70% , respectively. Two new genotypes MLMT-39 and -40 were found. Conclusion: In China , MLMT-17 of Cryptococcus neoformans var. grubii is prevalent in both clinical and environmental strains, implying the most clinical strains which resulted in cryptococcosis originated from indigenous environmental strains.

Key words: Cryptococcus neoformans var.grubii, multilocus microsatellite type