Functional polymorphism in the parental imprinting of the human IGF2R gene

Biochem Biophys Res Commun. 1993 Dec 15;197(2):747-54. doi: 10.1006/bbrc.1993.2542.


The murine genes coding for insulin-like growth factor II (Igf2) and its specific receptor (Igf2r) are parentally imprinted, with exclusive expression from the paternal (Igf2) or maternal (Igf2r) gene copy. We have demonstrated that the human IGF2 gene is imprinted, like its murine homologue. To examine whether the human IGF2R is also imprinted, we used CA repeat polymorphisms of the cDNA sequence to distinguish expression from each copy. Unlike the mouse, most subjects equally expressed both gene copies. However, two out of 14 informative fetuses showed exclusive expression from the maternal gene copy. We conclude that the human IGF2R gene is parentally imprinted, like its murine homologue, but only in a minority of individuals. This is the first direct demonstration of imprinting as a polymorphic trait, a property that had been observed in transgene methylation and predicted from the behavior of certain human tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • DNA / isolation & purification
  • DNA / metabolism
  • DNA Primers
  • Female
  • Fetus
  • Heterozygote
  • Hominidae / genetics*
  • Humans
  • Insulin-Like Growth Factor II / biosynthesis
  • Insulin-Like Growth Factor II / genetics*
  • Male
  • Mice
  • Molecular Sequence Data
  • Placenta / metabolism*
  • Polymerase Chain Reaction
  • Polymorphism, Genetic*
  • Pregnancy
  • Receptor, IGF Type 2 / biosynthesis
  • Receptor, IGF Type 2 / genetics*
  • Sequence Deletion


  • DNA Primers
  • Receptor, IGF Type 2
  • Insulin-Like Growth Factor II
  • DNA