Towards Unveiling the Genetics of Neurodegenerative Diseases

ABSTRACT

In addition to sharing several clinical, pathologic, and molecular characteristics, many neurodegenerative disorders show extensive familial histories suggesting a substantial contribution of genetic factors to disease causation and progression. In this review, the authors provide overviews of the status of current genetics research in Alzheimer's disease, Parkinson's disease, frontotemporal dementia, and amyotrophic lateral sclerosis. Across these four disorders alone, nearly 60 different loci can now be considered as established to be involved in pathogenesis for both Mendelian and non-Mendelian disease forms. In addition to reviewing the most compelling of these loci based on current data from genome-wide association studies and next-generation sequencing projects, genes that have been linked to more than one disease entity are emphasized. Such overlapping findings could point to one or several common genetic and mechanistic denominators for neuronal death in neurodegeneration. Unveiling the identity of these and other genetic factors will not only improve our understanding of the underlying pathophysiology, but may also lead to new avenues for preventing and treating these devastating diseases.

KEYWORDS

Neurodegeneration - neurodegenerative disease - genetics - mutation - polymorphism - Alzheimer's disease - Parkinson's disease - amyotrophic lateral sclerosis - frontotemporal dementia - AlzGene - PDGene - ALSGene - genome-wide association study - GWAS - meta-analysis

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