Based on reports in humans and dogs, markers for regulatory T cells (FoxP3 and CD25), proliferation/activation, (Ki67), (granzyme B), and functionality and T cell programming (IFN-γ) were feasible for a single panel and provided a diverse set of parameters for a preliminary assessment of T cell phenotyping of canine melanoma patients and controls. The gene discussed is MKI67; the disease is melanoma.