Recently, the Sleeping Beauty (SB) transposon system was shown to be an effective tool for functional genomics studies of solid tumor initiation, progression, and metastasis [48] When these mice were bred with transgenics for a concatemer of the T2/Onc transposon in a Ptch1+/− background, the Math1-SB11/T2Onc mice showed increased penetrance (39% to 97%) of MBs as well as decreased tumor latency (8 months to 2.5 months). This evidence concerns the gene PTCH1 and Mobius syndrome.