CD8A and dopa-responsive dystonia due to sepiapterin reductase deficiency: Other T cell groups include Killer CD8+ T cells, natural Killer T cells (NKT cells), Gamma-Delta T cells (γδ-T cells), and mucosal-associated invariant T (MAIT) cells – which have shown dysfunction in SRD – and again may be contributing to the phenotype of AGA positive SRD (Müller et al., 1998; Pellicci et al., 2020; Sperner-Unterweger et al., 1999; Varun et al., 2019; Wang et al., 2023).