HTT and Anxiety: Lastly, with high dose AAV5-miHTT treatment, which resulted in ∼90% lowering of mHTT and ∼95% lowering of wtHTT in the striatum as well as ∼65% lowering of mHTT and ∼ wtHTT in the cortex at 7 months post-injection, this magnitude of HTT suppression improved striatal atrophy, prevented onset of spatial learning deficits and blunted an anxiety-like phenotype in Hu128/21 mice.