Interferon-γ (IFN-γ) is essential in the immune response to mycobacterial infections, and a complete or partial deficiency in the IFN-γ receptor 1 (IFNγR1) or the IFN-γ receptor 2 (IFNγR2) have been reported to confer susceptibility to a disseminated infection with nontuberculous mycobacteria. However, similar mutations in the IFN-γ receptor have not been specifically examined in the patients with clinical tuberculosis.

This study searched for mutations in the IFN-γ receptor gene that resulted in a partial IFN-γ receptor deficiency in six patients with disseminated tuberculosis. The previously identified IFNγR1 and IFNγR2 coding regions were sequenced after amplification.

There was no partial IFNγR1 deficiency including a homozygous recessive missense mutation causing an amino-acid substitution in the extracellular domain of the receptor (I87T) and a hotspot for small deletions (818delT, 818del4, 818insA) found in any of the patients. In addition, a partial IFNγR2 deficiency of the homozygous missense mutation (R114C) was not found in any of the patients.

Genetic defects causing a partial IFN-γ receptor deficiency were not identified in our patients with disseminated tuberculosis.