Though all NB tumors expressed higher levels of TCF3-exon 18a transcripts than TCF3-exon 18b transcripts, those harboring amplification of MYCN exhibited a greater imbalance (Figure 3C), and most MYCN amplified NB cell lines expressed high levels of TCF3-18a transcripts (Figure 3D). The gene discussed is TCF3; the disease is neuroblastoma.