This can be done by screening MDR-TB with a GenoType MTBDRplus assay (Hain Lifescience GmbH, Nehren, Germany), which identifies inhA and/or katG. The research suggests that a mutation in the inhA region alone can exclude ethionamide from the MDR-TB empirical regimen, while adding high-dose isoniazid and paraaminosalicylic acid to the regimen. This evidence concerns the gene INHA and multidrug-resistant tuberculosis.