In a subgroup of 11 AHI, for whom DMSO-frozen PBMC samples were available, CD4+ and CD8+ T cell phenotypic profile (CD45RA, CCR7), markers of activation (CD38), exhaustion (PD-1), and senescence (CD57) were measured, and compared to those found in a control group of 13 HD. The gene discussed is CD38; the disease is Huntington disease.