A probe in biotechnology is a short, single-stranded DNA or RNA molecule used to detect a matching nucleic acid sequence in a sample. It is usually tagged with a detectable label so scientists can see where it binds.

Quick Scoop

  • What it does: A probe binds to its complementary DNA or RNA sequence through base pairing.
  • Why it matters: It helps identify, locate, or measure specific genes or genetic material in a sample.
  • How it is detected: The probe is often labeled with a radioactive, fluorescent, or chemical tag.

Common uses

  • Gene detection.
  • DNA fingerprinting and genetic testing.
  • Diagnostics for infections or inherited conditions.
  • Lab techniques like Southern blotting, Northern blotting, and in situ hybridization.

Simple example

If scientists want to find a gene linked to a disease, they can use a probe designed to match that gene’s sequence. If the probe binds, it shows that the target sequence is present.

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