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NCI Dictionary of Genetics Terms

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The NCI Dictionary of Genetics Terms contains technical definitions for more than 200 terms related to genetics. These definitions were developed by the PDQ® Cancer Genetics Editorial Board to support the evidence-based, peer-reviewed PDQ cancer genetics information summaries.

depth of coverage
(... KUH-veh-rij)
Refers to the number of times a nucleotide is read during sequencing. A greater depth of coverage can increase confidence in the final results. Deep coverage aids in differentiating sequencing errors from single nucleotide polymorphisms. This can be specifically useful when a patient has a mosaicism or when a tumor is heterogeneous for a mutation.