DNA ligase IV mutations identified in patients exhibiting developmental delay and immunodeficiency

Mol Cell. 2001 Dec;8(6):1175-85. doi: 10.1016/s1097-2765(01)00408-7.


DNA ligase IV functions in DNA nonhomologous end-joining and V(D)J recombination. Four patients with features including immunodeficiency and developmental and growth delay were found to have mutations in the gene encoding DNA ligase IV (LIG4). Their clinical phenotype closely resembles the DNA damage response disorder, Nijmegen breakage syndrome (NBS). Some of the mutations identified in the patients directly disrupt the ligase domain while others impair the interaction between DNA ligase IV and Xrcc-4. Cell lines from the patients show pronounced radiosensitivity. Unlike NBS cell lines, they show normal cell cycle checkpoint responses but impaired DNA double-strand break rejoining. An unexpected V(D)J recombination phenotype is observed involving a small decrease in rejoining frequency coupled with elevated imprecision at signal junctions.

Publication types

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

MeSH terms

  • Cell Cycle
  • Cell Cycle Proteins / physiology
  • Cells, Cultured
  • Child
  • Chromosome Breakage / genetics
  • DNA Damage / genetics
  • DNA Ligase ATP
  • DNA Ligases / genetics*
  • DNA Ligases / metabolism
  • DNA Mutational Analysis
  • DNA Repair / genetics
  • DNA-Binding Proteins / metabolism
  • Developmental Disabilities / enzymology
  • Developmental Disabilities / genetics*
  • Fibroblasts
  • Gene Rearrangement / genetics
  • Genetic Complementation Test
  • Humans
  • Immunologic Deficiency Syndromes / enzymology
  • Immunologic Deficiency Syndromes / genetics*
  • Middle Aged
  • Mutation / genetics*
  • Nuclear Proteins*
  • Phenotype
  • Protein Binding
  • Radiation Tolerance / genetics
  • Recombinant Proteins / metabolism
  • Recombination, Genetic / genetics
  • Syndrome
  • Transfection


  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • LIG4 protein, human
  • NBN protein, human
  • Nuclear Proteins
  • Recombinant Proteins
  • XRCC4 protein, human
  • DNA Ligases
  • DNA Ligase ATP