SLC6A3 and Huntington disease: Consistent with this, dopamine, homovanillic acid (HVA), the dopamine transporter (DAT), and the vesicular monoamine transporter‐2 (VMAT2) also have been reported to be reduced in HD striatum in late disease (Bohnen et al., 2000; Ginovart et al., 1997; Kish, Shannak, & Hornykiewicz, 1987; Suzuki et al., 2001).