Partial V(D)J recombination activity leads to Omenn syndrome

Cell. 1998 May 29;93(5):885-96. doi: 10.1016/s0092-8674(00)81448-8.

Abstract

Genomic rearrangement of the antigen receptor loci is initiated by the two lymphoid-specific proteins Rag-1 and Rag-2. Null mutations in either of the two proteins abrogate initiation of V(D)J recombination and cause severe combined immunodeficiency with complete absence of mature B and T lymphocytes. We report here that patients with Omenn syndrome, a severe immunodeficiency characterized by the presence of activated, anergic, oligoclonal T cells, hypereosinophilia, and high IgE levels, bear missense mutations in either the Rag-1 or Rag-2 genes that result in partial activity of the two proteins. Two of the amino acid substitutions map within the Rag-1 homeodomain and decrease DNA binding activity, while three others lower the efficiency of Rag-1/Rag-2 interaction. These findings provide evidence to indicate that the immunodeficiency manifested in patients with Omenn syndrome arises from mutations that decrease the efficiency of V(D)J recombination.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Clonal Anergy
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Eosinophilia
  • Female
  • Gene Rearrangement, T-Lymphocyte / genetics*
  • Genes, RAG-1
  • Genotype
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Humans
  • Lymphocyte Activation
  • Molecular Sequence Data
  • Mutation*
  • Nuclear Proteins
  • Protein Binding
  • Receptors, Antigen, T-Cell / genetics*
  • Recombination, Genetic*
  • Severe Combined Immunodeficiency / etiology*
  • Severe Combined Immunodeficiency / genetics
  • Syndrome

Substances

  • DNA-Binding Proteins
  • Homeodomain Proteins
  • Nuclear Proteins
  • RAG2 protein, human
  • Receptors, Antigen, T-Cell
  • V(D)J recombination activating protein 2
  • RAG-1 protein