Insitu hybridization is used for:(1994)
**Core Concept**
Insitu hybridization is a laboratory technique used to detect and locate specific nucleic acid sequences within a tissue section. It involves the use of a labeled complementary RNA or DNA probe that binds to the target nucleic acid sequence, allowing for the visualization of the hybridized probe through various detection methods.
**Why the Correct Answer is Right**
Insitu hybridization is a powerful tool in molecular pathology, allowing for the detection of specific gene expressions or viral infections within a tissue sample. The technique involves the use of a labeled probe that is complementary to the target nucleic acid sequence, which binds to the sequence through Watson-Crick base pairing. This binding event can be visualized through various detection methods, such as fluorescence or radioactive labeling.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because immunohistochemistry is a different laboratory technique used to detect specific proteins or antigens within a tissue sample, rather than nucleic acid sequences.
**Option B:** This option is incorrect because PCR (polymerase chain reaction) is a laboratory technique used to amplify specific nucleic acid sequences, but it does not involve the visualization of the sequences within a tissue sample.
**Option C:** This option is incorrect because flow cytometry is a laboratory technique used to analyze the properties of cells, but it is not used for the detection of nucleic acid sequences within a tissue sample.
**Clinical Pearl / High-Yield Fact**
Insitu hybridization is a sensitive and specific technique for detecting viral infections, such as human papillomavirus (HPV), within a tissue sample. It is often used in conjunction with histopathological examination to aid in the diagnosis of various diseases.
**Correct Answer:** D.