JUN and neoplasm: In LLC development, the abundance of fragments encoding tumour-specific genes was 15-fold higher in comparison with healthy mice (compare LLLC, Lh1 and Lh2, Table 4) and 90% of all fragments belonged to Myc. Thus, in tumour development the abundance of Myc-specific fragments rose 15-fold and the abundance of Hmga2-, Fos- and Jun-specific fragments rose two- to three-fold in comparison with healthy mice, whereas the abundance of Nras-specific fragments did not change (Table 4).