This model also afforded the opportunity to engraft NSG mice with PBMCs from healthy donors encoding either loss- or gain-of-function P2RX7 SNPs [249], but the comparison of a small number of donors and genotypes did not reveal any difference between the two groups, suggesting that the donor P2RX7 genotype does not influence GVHD development. The gene discussed is P2RX7; the disease is graft versus host disease.