Amplification of chromosomal bands 6p12‐p21 appeared to be significant in the pathogenesis of osteosarcoma, and CDC5L is found to be the most likely candidate oncogene for the 6p12-p21 amplicon 25.CDC5L was highly expressed in colon cancer cells and was correlated with cell growth and proliferation partially by regulating the PI3K/AKT signalling pathway. The gene discussed is AKT1; the disease is osteosarcoma.