Consistent with these results, we found no reduction of severity of GVHD in Ceacam1–/– compared with WT recipients, as suggested by the observation that there was little difference in body weight loss or diarrhea; and in both groups, approximately 40%–60% of the recipients died within 3 weeks after HCT (Figure 2C). The gene discussed is CEACAM1; the disease is graft versus host disease.