The size of Microsatellite repeat sequence is:
**Core Concept**
Microsatellites, also known as Short Tandem Repeats (STRs), are repetitive DNA sequences consisting of 2-5 base pairs that are repeated in tandem. These sequences are scattered throughout the human genome and are used as genetic markers for forensic analysis, genetic mapping, and disease diagnosis.
**Why the Correct Answer is Right**
The size of microsatellite repeat sequences typically ranges from 2 to 5 base pairs, with the most common sizes being 2, 3, or 4 base pairs. These short sequences are repeated in tandem, resulting in a variable number of repeats (VNTR) that can be used to identify individuals or diagnose genetic disorders. The length of the repeat sequence is critical in determining the genetic variation and its association with disease.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as microsatellites are typically shorter than 10 base pairs.
* **Option B:** This option is incorrect as it is too long for a typical microsatellite repeat sequence.
* **Option C:** This option is incorrect as it is not a common size for microsatellite repeat sequences.
**Clinical Pearl / High-Yield Fact**
Microsatellite instability (MSI) is a condition where the repeat sequences are unstable and can lead to genetic mutations, which are associated with various cancers and neurological disorders.
**Correct Answer: C. 2-5 base pairs.**