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Low copy number (LCN) DNA

Definition

An approach to analysing low-template samples by increasing the number of PCR amplification cycles, typically to 34 cycles. Increases sensitivity but also amplifies contaminants and stochastic noise, requiring strict quality controls and replicate analysis.

Related terms

Corneocyte
A terminally differentiated, anucleate cell forming the outermost skin layer (stratum corneum). Corneocytes shed continuously. Nucleated cells from deeper epidermal layers are...
Double-swab technique
A collection method for dried biological stains in which a moistened swab rehydrates and lifts the stain from the surface, followed immediately...
Secondary transfer
The movement of a glass fragment from a primary surface (which contacted the broken glass) to a secondary surface (which contacted the...
Stochastic effect
A random sampling artefact that occurs at very low template quantities. Examples include allelic dropout (an allele fails to amplify), allelic drop-in...
Touch DNA
Minute quantities of epithelial cells transferred by skin contact with a surface, without leaving a visible stain. Collected by swabbing contact points...

Explained in

  • Touch DNA and Trace Biological MaterialAn approach to analysing low-template samples by increasing the number of PCR amplification cycles, typically to 34 cycles. Increases sensitivity but also ampl...

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