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A small molecule of DNA or RNA that is designed to hybridise with a particular section of the genome.

Use in clinical context

Probes are a single-stranded sequence of DNA or RNA that is used to identify specific sequences of DNA or RNA. They are designed as complementary to the part of the genome of interest, so that when the probe and the genome are brought together, the probe will hybridise with the target sequence.

Probes are designed to be detected, and they are often modified to fluoresce or are radioactively labelled so that they can located easily

Probes are used in a number of clinical genomic tests, including fluorescent in situ hybridisation, quantitative PCR (where the amount of PCR product is measured) and microarrays.

Last updated on 17th November, 2021