In a recent study with humanized NSG mice, CD34+ hematopoietic progenitor cells (HSC) from HLA-DRB1*15-positive donors induced higher peripheral T cell responses and alloreactivity compared to HSC from HLA-DRB1*15-negative donors, and increased CD8+ T cell responses after EBV infection (Zdimerova et al., 2021). The gene discussed is HLA-DRB1; the disease is Epstein-Barr virus infection.