Ferdinand Séverine, Sola Christophe, Chanteau Suzanne, Ramarokoto Herimanana, Rasolonavalona Tiana, Rasolofo-Razanamparany Voahangy, Rastogi Nalin
Unité de la Tuberculose and des Mycobactéries, Institut Pasteur de Guadeloupe, Morne Joliviere, Pointe-à-Pitre, France.
Infect Genet Evol. 2005 Oct;5(4):340-8. doi: 10.1016/j.meegid.2004.10.002.
Despite well-developed tuberculosis (TB) control policies in Madagascar, the incidence of TB remains high and is estimated at about 100 new cases per 100000 inhabitants. This paper describes genetic characteristics of TB bacilli in Madagascar. Using an international spoligotyping database, SpolDB4, we also attempted to identify the origin of strains circulating in Madagascar. DNA polymorphism of 333 Mycobacterium tuberculosis complex isolates was assessed. A total of 301 isolates belonging to 60 spoligotyping-defined clusters were found, whereas 32 isolates harbored orphan patterns. By comparison with the international database, we identified a new genetic group of closely genetically related M. tuberculosis strains which we suggested to be specific from Madagascar. Most of them belonging to the East-African-Indian (EAI) superfamily of strains that are responsible for 14% of total TB cases (shared types ST1514-1525). These strains are closely related to the most prevalent shared type ST109, whose distribution is mainly confined to Madagascar. The observed distribution of genotypes shows that principal genetic group 1 strains (EAI, Beijing, CAS, Afri, "Manu") is high (35.4%) suggesting an ancient evolutionary history of tuberculosis in Madagascar, in relation to the origin of peopling and the demographic history.
尽管马达加斯加有完善的结核病控制政策，但结核病发病率仍然很高，估计每10万居民中约有100例新发病例。本文描述了马达加斯加结核杆菌的基因特征。我们还利用国际间隔寡核苷酸分型数据库SpolDB4，试图确定在马达加斯加传播的菌株的起源。评估了333株结核分枝杆菌复合群分离株的DNA多态性。共发现301株分离株属于60个由间隔寡核苷酸分型定义的簇，而32株分离株具有孤儿型。通过与国际数据库比较，我们鉴定出一组新的基因密切相关的结核分枝杆菌菌株，我们认为它们是马达加斯加特有的。其中大多数属于东非-印度（EAI）菌株超家族，该家族导致的结核病病例占总病例的14%（共享型ST1514-1525）。这些菌株与最常见的共享型ST109密切相关，其分布主要局限于马达加斯加。观察到的基因型分布表明，主要基因群1菌株（EAI、北京、CAS、非洲、“马努”）比例很高（35.4%），这表明马达加斯加的结核病有古老的进化史，与人口起源和人口历史有关。
