Genetic structure of black rat populations in a rural plague focus in Madagascar
Genetic structure of black rat populations in a rural plague focus in Madagascar
复制标题
DOI：
10.1139/z07-083
复制
发表时间：
2007-09-01
影响因子：
1.4
通讯作者：
Brouat, C.
中科院分区：
文献类型：
--
作者：
Gilabert, A.;Loiseau, A.;Brouat, C.
水库种群的遗传结构是理解传染病在自然系统中持续存在的关键特征。在马达加斯加高地，鼠疫自1920年以来一直持续存在，黑鼠Rattus Rattus(L.，1758)是唯一一种作为疾病宿主的物种。生态调查表明，马达加斯加鼠疫持续流行地区(海拔800米以上)的位置与一种地方性鼠疫媒介--方格氏跳蚤的分布区域之间存在明显的相关性，这种鼠疫媒介仅在生活在户外的老鼠身上发现。这种明显的栖息地隔离导致了中央高地鼠类种群被划分为室内和室外种群的建议。利用8个微卫星标记，分析了生活在鼠疫疫源地的鼠类种群的遗传结构与生境和地理距离的关系。我们发现，与地理距离不同，栖息地本身并不是一个结构性因素。然而，在精细空间尺度上发现的鼠类种群的显著基因分异可能与室内和室外栖息地鼠类种群动态的差异有关。
The genetic structure of reservoir populations is a key characteristic in understanding the persistence of infectious diseases in natural systems. In the Highlands of Madagascar, where plague has persisted since 1920, the black rat, Rattus rattus (L., 1758), is the sole species acting as a reservoir of the disease. Ecological surveys have shown a clear correlation between the locations of the plague-persistence area in Madagascar (above 800 m elevation) and the distribution area of one endemic plague vector, the flea Synopsyllus fonquerniei, which is found exclusively on rats living outdoors. This clear habitat segregation has led to the suggestion that R. rattus populations in the central highlands are divided into indoor- and outdoor-dwelling populations. Using eight microsatellite markers, we analysed the genetic structure of R. rattus populations living within a human plague focus in relation to habitat and geographic distance. We found that habitat by itself was not a structuring factor, unlike geographic distance. Nevertheless, the significant genotypic differentiation of R. rattus populations that was found at a fine spatial scale might relate to differences in population dynamics between rats in indoor and outdoor habitats.