What is the Difference Between Probe and Primer?

The main difference between a probe and a primer lies in their functions and properties in molecular biology:

• Probe:
• A probe is a small fragment of DNA or RNA used to detect the presence of a specific target sequence in a sample.
• Probes are single-stranded nucleotide sequences that are complementary to the target sequence.
• They can be labeled with fluorescent dyes or other chemicals for easy detection.
• Probes are used in techniques such as PCR (polymerase chain reaction) to identify target sequences.
• Primer:
• A primer is a small stretch of DNA or RNA that serves as a starting point for DNA synthesis.
• Primers are short, single-stranded nucleotide sequences that hybridize with single-stranded DNA.
• They are necessary for DNA replication, as DNA polymerase can only synthesize new DNA by adding nucleotides to the 3' end of an existing nucleotide.
• Primers are commonly used in techniques like PCR and DNA sequencing.

In summary, probes are used to detect the presence of specific target sequences, while primers serve as starting points for DNA synthesis and replication.

Comparative Table: Probe vs Primer

Here is a table comparing the differences between probes and primers:

Both probes and primers are single-stranded oligonucleotides used in various PCR techniques to hybridize with complementary DNA. They are specific to a particular DNA fragment, and both can be labeled with radioactive elements or fluorescence for detection purposes.