| 引用本文: | 卢琴,朱键,史荣兴,贺婷婷,张维.不同地区的142株新生隐球菌格鲁比变种MLMT分析[J].中国临床新医学,0,():-. |
| luqin,zhujian,shirongxing,hetingting.不同地区的142株新生隐球菌格鲁比变种MLMT分析[J].中国临床新医学,0,():-. |
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| 摘要: |
| 目的：分析不同地区的142株新生隐球菌格鲁比变种（Cryptococcus neoformans var. grubii）的多位点微卫星分型（Multilocus microsatellite typing，MLMT）基因型多样性及区域分布特征。方法：对中、日、巴西三地菌株提取DNA，采用CNG1（TA）、CNG2（GA）、CNG3（CAT）微卫星位点引物扩增测序，通过Chromas软件计算基序重复数确定基因型，辛普森指数评估基因型多样性，合并低频基因型类别（将总频数小于5的基因型合并为“其他”类别），卡方检验或Fisher精确检验比较地区间的基因型分布差异。结果：142株菌株分为17种MLMT基因型，中国检出7型（MLMT-14、16、17、29、34、39、40），日本2型（MLMT-2、17），巴西13型（MLMT-2、12-14、17、31-38）。三地辛普森指数分别为中国0.32、日本0.15、巴西0.82，东亚（中国、日本）菌株（D=0.58），巴西基因型多样性显著高于东亚，并且区域间基因型分布具有统计学差异（P＜0.05），中日基因型分布一致（P=0.287）；142株中临床和环境菌株基因型分布出现显著差异（p＜0.05）, 临床菌株以基因型MLMT-13、17为主，环境菌株以基因型MLMT-17、36为主，在临床与环境菌株中MLMT-2、34属于中性型。结论：MLMT方法具有分辨力高、操作简单、速度快、成本低的优点，研究通过MLMT分析新生隐球菌格鲁比变种基因型多样性存在地域差异，东亚地区基因型以MLMT-17为主，巴西地区基因型以MLMT-36为主，巴西地区基因型呈现高度遗传多样性，地区间基因型分布模式呈现显著差异，未来研究需结合更大样本及多因素分析研究地理与来源的交互作用或深入分析基因型13、17、36的功能意义。 |
| 关键词: 新型隐球菌格鲁比变种 多位点微卫星分型 基因型多样性 地理分布 适应性进化 |
| DOI： |
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| 基金项目:贵州省卫生健康委员会科学技术(gzwkj2013－1－055) |
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| MLMT Analysis of 142 Cryptococcus neoformans var. grubii Isolates from Geographically Diverse Regions |
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luqin,zhujian,shirongxing,hetingting
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贵州医科大学
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| Abstract: |
| Objective: To analyze multilocus microsatellite typing (MLMT) genotypic diversity and regional distribution characteristics of 142 Cryptococcus neoformans var. grubii isolates from different regions. Methods: DNA was extracted from strains collected in China, Japan, and Brazil. MLMT was performed using CNG1 (TA), CNG2 (GA), and CNG3 (CAT) microsatellite loci. Genotypes were determined by sequence analysis using Chromas software. The Simpson index was used to assess genotypic diversity. Low-frequency genotypes were grouped into categories. CNG3 (CAT) microsatellite loci. Genotypes were determined by counting motif repeats using Chromas software, and genotypic diversity was assessed using the Simpson index. Low-frequency genotypes were grouped into an “other” category (for those with a total frequency <5). Regional differences in genotype distribution were compared using chi-square or Fisher's exact tests. Results: 142 strains were classified into 17 MLMT genotypes. China detected 7 types (MLMT-14, 16, 17, 29, 34, 39, 40), Japan 2 types (MLMT-2, 17), and Brazil 13 types (MLMT-2, 12-14, 17, 31-38). The Simpson indices for the three regions were 0.32 for China, 0.15 for Japan, and 0.82 for Brazil. East Asian strains (China and Japan) showed a lower index (D=0.58). Brazil exhibited significantly higher genotype diversity than East Asia, with statistically significant differences in genotype distribution between regions (P<0.05). Genotype distributions in China and Japan were consistent (P=0.287). Significant differences (p<0.05) were observed in genotype distribution between clinical and environmental strains among the 142 isolates. Clinical strains predominantly exhibited genotypes MLMT-13 and 17, while environmental strains showed MLMT-17 and 36 as the main genotypes. Genotypes MLMT-2 and 34 were neutral in both clinical and environmental isolates. Conclusion: The MLMT method offers high resolution, simplicity, speed, and low cost. This study demonstrated regional variation in genotypic diversity of Cryptococcus neoformans var. glubii through MLMT analysis. East Asia predominantly exhibited the MLMT-17 genotype, while Brazil primarily showed the MLMT-36 genotype. Brazil exhibited high genetic diversity, with significant differences in genotypic distribution patterns between regions. Future studies should incorporate larger samples and multifactorial analyses to investigate the interaction between geography and origin, or conduct in-depth functional analyses of genotypes 13, 17, and 36. |
| Key words: Cryptococcus neoformans var. grubii Multilocus microsatellite typing (MLMT) Genotype Diversity Geographical distribution adaptive evolution |
