Notably, about 1% to 5% of newborns are reported to carry ETV6-RUNX1 gene fusions in approximately 1 in 10,000 B lymphoid lineage cells (although this varies considerably amongst different studies) without overt B cell precursor ALL developing in the vast majority of these children, and with predisposing factors for development of B cell precursor ALL post-natally, including environmental factors and additional mutations [6,121,122,124,141,142,143,144,145,146,147,148]. Here, RUNX1 is linked to acute lymphoblastic leukemia.