IFNG and leprosy: Seven works are related to the area of Diagnosis, proposing: (a) the identification of leprosy through binary classification (leprosy/non-leprosy) [33,35,45]; (b) the identification of the disease’s operational classification (paucibacillary (PB)/multibacillary(MB)) [27]; (c) the identification of genetic characteristics of leprosy patients [44]; (d) the diagnosis of subclinical leprosy cases, based on the patient’s ability to induce the production of IFN-γ [54]; and (e) to invesigating Bacterial Volatilome [55].