We found a drop of HD5 expression in patients with severe acute GI GvHD from 7.1 (8.7x10-5 to 8.0x101) to 3.2x10-2 (1.8x10-4 to 1.6x101, p = 0.004), for HD6 from 5.1 (1.3x10-4 to 2.2x102) to 6.0x10-2 (3.6x10-4 to 3.0x101, p = 0.006) and for Reg3α from 1.1x101 (5.1x10-4 to 3.3x102) to 6.6x10-2 (1.2x10-4 to 5.2x101, p = 0.012), respectively. This evidence concerns the gene REG3A and graft versus host disease.