Mutations in GDI1 are responsible for X-linked non-specific mental retardation

Nat Genet. 1998 Jun;19(2):134-9. doi: 10.1038/487.


Rab GDP-dissociation inhibitors (GDI) are evolutionarily conserved proteins that play an essential role in the recycling of Rab GTPases required for vesicular transport through the secretory pathway. We have found mutations in the GDI1 gene (which encodes uGDI) in two families affected with X-linked non-specific mental retardation. One of the mutations caused a non-conservative substitution (L92P) which reduced binding and recycling of RAB3A, the second was a null mutation. Our results show that both functional and developmental alterations in the neuron may account for the severe impairment of learning abilities as a consequence of mutations in GDI1, emphasizing its critical role in development of human intellectual and learning abilities.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Brain / embryology
  • Crystallography, X-Ray
  • Embryonic and Fetal Development / genetics
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism
  • GTP-Binding Proteins / genetics*
  • GTP-Binding Proteins / metabolism
  • GTP-Binding Proteins / physiology
  • Genetic Linkage
  • Guanine Nucleotide Dissociation Inhibitors*
  • Humans
  • Intellectual Disability / genetics*
  • Models, Molecular
  • Mutagenesis, Site-Directed
  • Mutation*
  • Nerve Tissue Proteins / metabolism
  • Polymorphism, Single-Stranded Conformational
  • Protein Conformation
  • Proto-Oncogene Proteins / metabolism
  • X Chromosome
  • rab3 GTP-Binding Proteins


  • GDP dissociation inhibitor 1
  • Guanine Nucleotide Dissociation Inhibitors
  • Nerve Tissue Proteins
  • Proto-Oncogene Proteins
  • GTP Phosphohydrolases
  • GTP-Binding Proteins
  • rab3 GTP-Binding Proteins