University of Sussex
Browse

File(s) not publicly available

Analysis of DNA ligase IV mutations found in LIG4 syndrome patients: the impact of two linked polymorphisms

journal contribution
posted on 2023-06-08, 05:25 authored by Pierre-Marie Girard, Boris Kysela, Christine J Härer, Aidan DohertyAidan Doherty, Penny Jeggo
LIG4 syndrome patients have hypomorphic mutations in DNA ligase IV. Although four of the five identified patients display immunodeficiency and developmental delay, one patient was developmentally normal. The developmentally normal patient had the same homozygous mutation (R278H) in DNA ligase IV as one of the more severely affected patients, who additionally had two linked polymorphisms. Here, we examine the impact of the mutations and polymorphisms identified in the LIG4 syndrome patients. Examination of recombinant mutant proteins shows that the severity of the clinical features correlates with the level of residual ligase activity. The polymorphisms decrease the activity of DNA ligase IV by ~2-fold. When combined with the otherwise mild R278H mutation, the activity is reduced to a level similar to other LIG4 patients who display immunodeficiency and developmental delay. This demonstrates how coupling of a mutation and polymorphism can have a marked impact on protein function and provides an example where a polymorphism may have influenced clinical outcome. Analysis of additional mutational changes in LIG4 syndrome (R580X, R814X and G469E) have led to the identification of a nuclear localization signal in DNA ligase IV and sites impacting upon DNA ligase IV adenylation.

History

Publication status

  • Published

Journal

Human Molecular Genetics

ISSN

0964-6906

Issue

20

Volume

13

Page range

2369-2376

Pages

8.0

Department affiliated with

  • Sussex Centre for Genome Damage Stability Publications

Full text available

  • No

Peer reviewed?

  • Yes

Legacy Posted Date

2012-02-06

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC