Considering that FeLV is known to replicate in the bone marrow [26,27], and that FeLV-945 infection was associated with various diseases of hematopoietic origin [Chandhasin et al., manuscript submitted], it is likely that the tropism of FeLV-945 in vivo included the hematopoietic progenitors in which c-Myb is expressed. This evidence concerns the gene MYB and infection.