- No evidence for correlation of DDX1 gene amplification with improved survival probability in patients with MYCN-amplified neuroblastomas. De Preter, K., Speleman, F., Combaret, V., Lunec, J., Board, J., Pearson, A., De Paepe, A., Van Roy, N., Laureys, G., Vandesompele, J. J. Clin. Oncol. (2005)