We and others have reported the progression mechanism of ATLL from various genetic aspects, including specific chromosome abnormalities [77-82], changes of characteristic HTLV-I Tax and Rex protein expression patterns [71] and aberrant expression of the SHP1 [78,83], P53 [84,85],MELIS [85], DRS [86] and ASY/Nogo [87] genes, although the detailed mechanism triggering the onset and progression of ATLL remains to be elucidated. Here, TP53 is linked to adult T-cell leukemia/lymphoma.