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Updated: May 28, 2026
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VDJ-Seq: Deep Sequencing Analysis of Rearranged Immunoglobulin Heavy Chain Gene to Reveal Clonal Evolution Patterns of B Cell Lymphoma
Published on: December 28, 2015
Omenn syndrome does not live by V(D)J recombination alone
Veronica Marrella1, Virginia Maina, Anna Villa
1Institute of Genetic and Biomedical Research, Milan Unit, National Research Council (CNR), Milan bIstituto Clinico Humanitas IRCCS, Rozzano, Italy.
Current Opinion in Allergy and Clinical Immunology
|October 18, 2011
Summary
Omenn syndrome, a severe combined immunodeficiency, involves skin erythroderma and colitis due to impaired V(D)J recombination. Genetic defects beyond recombination activating gene (RAG) mutations also cause Omenn-like disorders.
Area of Science:
- Immunology
- Genetics
- Molecular Biology
Background:
- Severe combined immunodeficiencies (SCIDs) are a group of genetic disorders affecting immune system development.
- Omenn syndrome is a specific SCID phenotype characterized by erythroderma, T-cell activation, and elevated IgE.
Purpose of the Study:
- To review the expanding clinical and immunological spectrum of Omenn syndrome.
- To explore the cellular and molecular mechanisms underlying classical Omenn syndrome and Omenn-like disorders.
Main Methods:
- Review of recent studies on Omenn syndrome pathogenesis.
- Analysis of genetic mutations associated with Omenn phenotype.
- Examination of cellular and molecular mechanisms.
Main Results:
- Omenn phenotype is linked to mutations in V(D)J recombination genes (e.g., RAG genes) and other lymphoid maturation genes.
- Classical Omenn syndrome results from hypomorphic RAG gene defects.
- Omenn-like features can arise from mutations outside of V(D)J recombination pathways.
Conclusions:
- Impaired V(D)J recombination generates a limited number of T cells that cause inflammation in target organs like skin and gut.
- Omenn syndrome is an inflammatory condition with diverse genetic underpinnings, not solely limited to V(D)J recombination defects.
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