Ebers G C, Sadovnick A D
Neuroepidemiology. 1993;12(1):1-5. doi: 10.1159/000110293.
The decisive conclusions to be drawn from the geography and prevalence of MS are: (1) a north-south (as well as west-east in the United States) gradient exists independent from genetic/racial factors; (2) major differences in prevalence occur in the absence of difference in latitude; (3) individuals from the same ethnic derivation have either the similar prevalence or have very different prevalence rates in widely separated geographical areas, and (4) specific resistance isolates are shown to exist regardless of latitude. Existing prevalence information leads to the almost inescapable conclusion that the geography of MS cannot be explained by any single known environmental or genetic factor(s) in isolation. A combination of a heterogeneous distribution of both genetic and environmental factors appears to be required to explain the available data on MS and geography.
（1）存在一个独立于遗传/种族因素的南北梯度（在美国还有东西梯度）；（2）在纬度没有差异的情况下，患病率存在重大差异；（3）来自同一族裔的个体在广泛分隔的地理区域中，患病率要么相似，要么差异很大；（4）无论纬度如何，都显示存在特定的抗性隔离区。现有的患病率信息几乎不可避免地得出这样的结论：多发性硬化症的地理分布无法用任何单一已知的环境或遗传因素单独解释。似乎需要遗传和环境因素的异质分布相结合，才能解释关于多发性硬化症和地理分布的现有数据。
