Noteworthy, the Tc1 model is trisomic for approximately 80% of the genes encoded on Hsa21, but not for RUNX1, ruling out its involvement in the observed Tc1 hematopoietic alterations, but allowing for the speculation of whether its triplication could still lead to a more aggressive myeloproliferative disease in this paradigm. The gene discussed is RUNX1; the disease is myeloproliferative disorder.