DICER1 and toxic multinodular goitre: Based on observations that pleuropulmonary blastoma (PPB) families also have MNG, Rio Frio et al. screened mutations of the PPB-causative gene dicer 1, ribonuclease type III (DICER1), which is located in the MNG-1 locus in MNG families, and identified several mutations linked to MNG [16].