GNAS and neoplasm: This hypothesis was supported by transgenic mouse studies described above and previous studies demonstrating mutations of several oncogenes (ras, TRK, and gsp), tumour supperssor genes such as FHIT, and mitochondrial genes in benign MNG (Shi et al, 1991; Farid et al, 1995; Zou et al, 1999; Abu-Amero et al, 2005).