Multiple molecular abnormalities have been described in thyroid cancers arising from ovarian teratomas, including point mutations in BRAF (V600E and K601E) 67% of cases [13] and KRAS and NRAS [13] as well as loss of heterozigocity in the PTEN region and ret/PTC rearrangements [12, 13]. The gene discussed is PTEN; the disease is thyroid cancer.