Tissue-specific and mosaic imprinting defects underlie opposite congenital growth disorders in mice

PLoS Genet. 2018 Feb 22;14(2):e1007243. doi: 10.1371/journal.pgen.1007243. eCollection 2018 Feb.


Differential DNA methylation defects of H19/IGF2 are associated with congenital growth disorders characterized by opposite clinical pictures. Due to structural differences between human and mouse, the mechanisms by which mutations of the H19/IGF2 Imprinting Control region (IC1) result in these diseases are undefined. To address this issue, we previously generated a mouse line carrying a humanized IC1 (hIC1) and now replaced the wildtype with a mutant IC1 identified in the overgrowth-associated Beckwith-Wiedemann syndrome. The new humanized mouse line shows pre/post-natal overgrowth on maternal transmission and pre/post-natal undergrowth on paternal transmission of the mutation. The mutant hIC1 acquires abnormal methylation during development causing opposite H19/Igf2 imprinting defects on maternal and paternal chromosomes. Differential and possibly mosaic Igf2 expression and imprinting is associated with asymmetric growth of bilateral organs. Furthermore, tissue-specific imprinting defects result in deficient liver- and placenta-derived Igf2 on paternal transmission and excessive Igf2 in peripheral tissues on maternal transmission, providing a possible molecular explanation for imprinting-associated and phenotypically contrasting growth disorders.

Publication types

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

MeSH terms

  • Animals
  • Cells, Cultured
  • Female
  • Genomic Imprinting / genetics*
  • Growth Disorders / congenital*
  • Growth Disorders / genetics*
  • Humans
  • Insulin-Like Growth Factor II / genetics
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Mosaicism*
  • Mouse Embryonic Stem Cells
  • Mutation
  • Organ Specificity / genetics
  • Phenotype
  • Pregnancy
  • RNA, Long Noncoding / genetics


  • H19 long non-coding RNA
  • RNA, Long Noncoding
  • Insulin-Like Growth Factor II