Unraveling the complex interplay between genes, environment, and climate in ALS
Rosario Vasta,
Ruth Chia,
Bryan J. Traynor,
Adriano Chiò
Affiliations
Rosario Vasta
ALS Center, Department of Neuroscience ''Rita Levi Montalcini'', University of Turin, via Cherasco 15, Turin 1026, Italy; Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging (NIH), Bethesda, MD 20892, USA
Ruth Chia
Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging (NIH), Bethesda, MD 20892, USA
Bryan J. Traynor
Neuromuscular Diseases Research Section, Laboratory of Neurogenetics, National Institute on Aging (NIH), Bethesda, MD 20892, USA; Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, University College London, London WC1N 1PJ, UK; Department of Neurology, Johns Hopkins University Medical Center, Baltimore, MD 21287, USA; National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA; ASO Rapid Development Laboratory, Therapeutics Development Branch, National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
Adriano Chiò
ALS Center, Department of Neuroscience ''Rita Levi Montalcini'', University of Turin, via Cherasco 15, Turin 1026, Italy; Institute of Cognitive Sciences and Technologies, C.N.R., Rome 00185, Italy; Neurology 1, AOU Città della Salute e della Scienza di Torino, Turin, Italy; Corresponding author at: ALS Center, Department of Neuroscience ''Rita Levi Montalcini'', University of Turin, via Cherasco 15, Turin 1026, Italy.
Summary: Various genetic and environmental risk factors have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). Despite this, the cause of most ALS cases remains obscure. In this review, we describe the current evidence implicating genetic and environmental factors in motor neuron degeneration. While the risk exerted by many environmental factors may appear small, their effect could be magnified by the presence of a genetic predisposition. We postulate that gene-environment interactions account for at least a portion of the unknown etiology in ALS. Climate underlies multiple environmental factors, some of which have been implied in ALS etiology, and the impact of global temperature increase on the gene-environment interactions should be carefully monitored. We describe the main concepts underlying such interactions. Although a lack of large cohorts with detailed genetic and environmental information hampers the search for gene-environment interactions, newer algorithms and machine learning approaches offer an opportunity to break this stalemate. Understanding how genetic and environmental factors interact to cause ALS may ultimately pave the way towards precision medicine becoming an integral part of ALS care.
