Eth-A gene mutation can lead to cross resistance of Ethionamide with:: (A) PAS, (B) Isoniazid, (C) Ethambutol, (D) Thioacetazone
Answer is D. Eth-A gene encodes Monoxygenase enzyme that activates both Ethionamide and Thioacetazone. Therefore mutation of Eth-A gene is responsible for resistance in both Ethionamide and Thioacetazone.