AHCY and Huntington disease: Regarding the molecular mechanisms involved, s-adenosylhomocysteine (SAH) can inhibit PRMTs, and s-adenosylhomocysteine hydrolase (SAHH), which hydrolyses SAH to homocysteine and adenosine, is downregulated in the leukocytes of patients with HD and the striatal region of mouse models of HD [106].