Gene expe used for getting diagnosis of TB in ?
**Core Concept**
The question is testing the knowledge of molecular diagnostic techniques used in the diagnosis of tuberculosis (TB). The correct answer is related to a specific gene that is used as a marker for TB diagnosis.
**Why the Correct Answer is Right**
The correct answer is _Mycobacterium tuberculosis_ (MTB) gene, specifically the _IS6110_ gene, which is a repetitive element found in the genome of MTB. This gene is used as a target for PCR (polymerase chain reaction) to diagnose TB. The _IS6110_ gene is a member of the insertion sequence family and is highly conserved among MTB strains. The PCR technique amplifies the _IS6110_ gene, allowing for the detection of MTB DNA in clinical samples.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is likely a distractor, as there is no widely recognized gene that is used specifically for TB diagnosis.
* **Option B:** This option might be a distractor, as while MTB does have other genes that are targets for molecular diagnostics, _IS6110_ is the most commonly used gene for TB diagnosis.
* **Option C:** This option is incorrect, as while _Mycobacterium bovis_ is a close relative of MTB, it is not the primary target for TB diagnosis.
**Clinical Pearl / High-Yield Fact**
Molecular diagnostic techniques, such as PCR, have revolutionized the diagnosis of TB by providing rapid and accurate results. The use of the _IS6110_ gene as a target for PCR has become a gold standard for TB diagnosis in many settings.
**Correct Answer: D. IS6110 gene**