Engraftment of bone marrow from donors irradiated 0 or 12 months prior to harvest (1 Gy).

Male bone marrow was harvested 0 or 12 months after WBI and transplanted in 1 Gy–treated female hosts. Engraftment was measured by FISH for Y chromosomes at 8 weeks after transplantation. Controls consisted of nonirradiated donors transplanted in 1 Gy–treated recipients. Engraftments measured for time 0 and 12 months were significantly different from each other and from controls. Mean ± SE is shown (n = 5). There is no age-matched control for these studies.