In recent decades, the prevalence of inborn errors of immunity has increased, necessitating the development of more effective treatment and care options for these highly morbid conditions. Due to these “experiments of nature,” the complicated nature of the immune system is being revealed. Based on the functional and molecular tests, targeted therapies are now being developed which offer a more effective approach and reduce damage. This study aimed to investigate a key cytokine of the cellular immune response, interferon‐gamma (IFN-γ), which is linked to Mendelian susceptibility to Mycobacterial disease, and its potential as a therapeutic option for IFN-γ deficiency.