A comprehensive epigenetic analysis of the C9orf72 promoter in the context of Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a devastating multisystemic and neuromuscular disease with no cure. The aberrant microsatellite expansion of the C9orf72 gene, discovered in 2011, is the cause of the most frequent form of familial ALS, being responsible for gain of function and loss of function pathogenic mechanisms. The latter is about the silencing of the promoter, and 30% of patients show promoter hypermethylation and milder disease manifestation. So far, little is known about the epigenetic status of the C9orf72 promoter in different experimental models of the disease. My project aims to study the epigenetic status of 6 CCGG sites of the C9orf72 promoter on three in vitro disease models and on C9-BAC mice. In particular, I characterized the promoter through an exploratory in silico analysis. Then, I studied the methylation and hydroxymethylation status of the promoter on immortalised fibroblasts, myoconverted fibroblasts and on iPSC-derived motor neurons to see whether there were specific differences between pathological and normal contexts. Moreover, I analysed the epigenetic status of the same CCGG sites on C9-BAC mouse brains to study differences between heterozygous and homozygous conditions. The results will be the base for innovative epigenetic therapies for this devastating disease.