This hypothesis has been recently sustained by in vivo studies in Patz1-ko mice mated with mice transgenic for the thyroid specific oncogene RET/PTC1, which showed that homozygous deletion of the Patz1 gene worsens the thyroid cancer outcome in RET/PTC1 mice, by inducing the development of anaplastic thyroid carcinomas (ATC) and solid variants of papillary thyroid carcinomas (PTC) [18]. The gene discussed is PATZ1; the disease is thyroid gland undifferentiated (anaplastic) carcinoma.