Unusual phenotypes in patients with a pathogenic germline variant in DICER1

Fam Cancer. 2023 Oct;22(4):475-480. doi: 10.1007/s10689-021-00271-z. Epub 2021 Jul 31.


Pathogenic germline DICER1 variants are associated with pleuropulmonary blastoma, multinodular goiter, embryonal rhabdomyosarcoma and other tumour types, while mosaic missense DICER1 variants in the RNase IIIb domain are linked to cause GLOW (global developmental delay, lung cysts, overgrowth, and Wilms' tumor) syndrome. Here, we report four families with germline DICER1 pathogenic variants in which one member in each family had a more complex phenotype, including skeletal findings, facial dysmorphism and developmental abnormalities. The developmental features occur with a variable expressivity and incomplete penetrance as also described for the neoplastic and dysplastic lesions associated with DICER1 variants. Whole exome sequencing (WES) was performed on all four cases and revealed no further pathogenic or likely pathogenic dominant, homozygous or compound heterozygous variants in three of them. Notably, a frameshift variant in ARID1B was detected in one patient explaining part of her phenotype. This series of patients shows that pathogenic DICER1 variants may be associated with a broader phenotypic spectrum than initially assumed, including predisposition to different tumours, skeletal findings, dysmorphism and developmental abnormalities, but genetic work up in syndromic patients should be comprehensive in order not to miss additional underlying /modifying causes.

Keywords: DICER1; Developmental delay; Pierre-Robin sequence; Skeletal findings; Unusual phenotype.

Publication types

  • Research Support, N.I.H., Intramural
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cysts*
  • DEAD-box RNA Helicases / genetics
  • Female
  • Frameshift Mutation
  • Germ Cells
  • Germ-Line Mutation*
  • Humans
  • Phenotype
  • Ribonuclease III / genetics


  • Ribonuclease III
  • DICER1 protein, human
  • DEAD-box RNA Helicases