Differently from HD, where the SARS-CoV-2 mRNA vaccine elicits a potent adaptive immune response in the absence of IFN-mediated inflammation [24], the CVID non-responders had a high frequency of CD8+IFNγ+ T-cells, indicating a TH1-driven immune dysregulation [7,16,25] but also a defective IFNγ release by Spike peptide-stimulated cells. Here, IFNG is linked to Huntington disease.