Department of Infectious Diseases, Institute for Infectious Diseases, Guangzhou No. 8 People's Hospital, Guangzhou, Guangdong 510060, China.
Chin Med J (Engl). 2012 Mar;125(5):823-7.
Penicillium marneffei (P. marneffei) is an emerging pathogenic fungus that can cause invasive mycosis in patients with AIDS. The epidemiological features of P. marneffei infection in AIDS patients in Guangdong province remain unclear so far. This study aimed to investigate the genetic diversity within a population of 163 P. marneffei isolates obtained from AIDS patients and search for the dominant clinical strains in Guangdong province.
One hundred and sixty-three P. marneffei isolates obtained from AIDS patients in Guangdong province during January 2004 and December 2009 were studied by randomly amplified polymorphic DNA (RAPD) using two random primers (H2 and H22). The degree of similarity between samples was calculated through similarity coefficients from RAPD fragment data and the dendrogram was assessed using the unweighted pair group method with arithmetic mean (UPGMA).
Two primers showed a high degree of discrimination and good stability. Primer H2 yielded eight different patterns (H2-1 to H2-8) among 163 isolates with the discriminatory power being 0.413. Primer H22 identified seven types (H22-1 to H22-7) among 163 isolates with the discriminatory power being 0.467. Genetic similarity coefficients based on RAPD data among 163 P. marneffei isolates ranged from 0.681 to 0.957, 61.96% of which were no less than 0.83. The discriminatory power of the two primers was 0.524. One hundred and sixty-three P. marneffei isolates were clustered into nine distinct groups (groups I to IX) at the similarity coefficient value of 0.83 and group I was the most common, including 101 strains (61.96%).
The RAPD analyses could provide important information as to the degree of genetic diversity and the relationship among clinical P. marneffei isolates, revealing genetic polymorphism and dominant strains.
马尔尼菲青霉（Penicillium marneffei，P. marneffei）是一种新兴的致病真菌，可导致艾滋病患者发生侵袭性真菌感染。目前，广东省艾滋病患者中马尔尼菲青霉感染的流行病学特征尚不清楚。本研究旨在调查从艾滋病患者中分离到的 163 株马尔尼菲青霉种群的遗传多样性，并寻找广东省的优势临床菌株。
采用随机扩增多态性 DNA（RAPD）技术，使用 2 个随机引物（H2 和 H22）对 2004 年 1 月至 2009 年 12 月期间从广东省艾滋病患者中分离得到的 163 株马尔尼菲青霉进行研究。通过 RAPD 片段数据的相似系数计算样本之间的相似度，并采用算术平均非加权对组法（UPGMA）构建聚类树状图。
这 2 个引物具有较高的分辨能力和良好的稳定性。引物 H2 在 163 株分离株中产生了 8 种不同的图谱（H2-1 至 H2-8），分辨力为 0.413。引物 H22 在 163 株分离株中识别出 7 种类型（H22-1 至 H22-7），分辨力为 0.467。基于 RAPD 数据的 163 株马尔尼菲青霉遗传相似系数范围为 0.681 至 0.957，其中 61.96%不低于 0.83。这 2 个引物的分辨力为 0.524。在相似系数为 0.83 时，163 株马尔尼菲青霉分离株聚类为 9 个不同的群组（群组 I 至 IX），其中群组 I 最为常见，包括 101 株（61.96%）。
RAPD 分析可提供有关临床马尔尼菲青霉分离株遗传多样性和相互关系的重要信息，揭示遗传多态性和优势菌株。
