BDNF and Huntington disease: It is important to remember, however, that interfering with epigenetic mechanism might prove to be a double-edged sword, that on the one hand improves some aspects of HD pathology (e.g., reduced trinucleotide repeat instability and improved BDNF levels), while on the other hand makes other aspects worse (e.g., increased instability of LINE-1 elements and hypomethylation of HTT that correlates with disease progression).