Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA.
Amyotroph Lateral Scler Frontotemporal Degener. 2013 Sep;14(5-6):325-33. doi: 10.3109/21678421.2012.750364. Epub 2013 Jan 4.
There is a broad scientific consensus that amyotrophic lateral sclerosis (ALS) is caused by gene-environment interactions. Mutations in genes underlying familial ALS (fALS) have been discovered in only 5-10% of the total population of ALS patients. Relatively little attention has been paid to environmental and lifestyle factors that may trigger the cascade of motor neuron death leading to the syndrome of ALS, although exposure to chemicals including lead and pesticides, and to agricultural environments, smoking, certain sports, and trauma have all been identified with an increased risk of ALS. There is a need for research to quantify the relative roles of each of the identified risk factors for ALS. Recent evidence has strengthened the theory that chronic environmental exposure to the neurotoxic amino acid β-N-methylamino-L-alanine (BMAA) produced by cyanobacteria may be an environmental risk factor for ALS. Here we describe methods that may be used to assess exposure to cyanobacteria, and hence potentially to BMAA, namely an epidemiologic questionnaire and direct and indirect methods for estimating the cyanobacterial load in ecosystems. Rigorous epidemiologic studies could determine the risks associated with exposure to cyanobacteria, and if combined with genetic analysis of ALS cases and controls could reveal etiologically important gene-environment interactions in genetically vulnerable individuals.
科学界普遍认为肌萎缩侧索硬化症（ALS）是由基因-环境相互作用引起的。在总 ALS 患者群体中，仅发现了 5-10%的家族性 ALS（fALS）患者存在基因突变。尽管已经确定了一些环境和生活方式因素可能引发导致 ALS 综合征的运动神经元死亡级联反应，例如接触包括铅和杀虫剂在内的化学物质，以及农业环境、吸烟、某些运动和创伤，都会增加患 ALS 的风险，但相对较少关注可能触发该级联反应的环境和生活方式因素。需要研究来量化每个已确定的 ALS 风险因素的相对作用。最近的证据加强了这样一种理论，即慢性暴露于蓝藻产生的神经毒性氨基酸β-N-甲基氨基-L-丙氨酸（BMAA）可能是 ALS 的环境风险因素。在这里，我们描述了评估接触蓝藻（从而可能评估 BMAA）的方法，即流行病学问卷以及直接和间接方法来估计生态系统中的蓝藻负荷。严格的流行病学研究可以确定与接触蓝藻相关的风险，如果结合 ALS 病例和对照的基因分析，可以揭示在遗传易感性个体中具有病因学重要意义的基因-环境相互作用。
