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Stochastic Effects

Definition

Random sampling errors arising when few template molecules are present in a PCR reaction. Manifest as allele drop-out, allele drop-in, elevated stutter and peak-height imbalance.

Related terms

Allele Drop-in
Appearance of a low-level allele in a PCR product from stochastic amplification of a contaminant molecule. More common in low-template reactions where...
Allele Drop-Out
Failure of one allele at a heterozygous locus to amplify in a low-template PCR reaction, producing an apparent homozygote. Increases dramatically below...
EDTA Decalcification
Demineralisation of bone powder using 0.5 M EDTA at pH 8.0, which chelates calcium from hydroxyapatite and releases DNA from the mineral...
Petrous Bone
The petrous portion of the temporal bone, the densest bone in the human skull. Its dense hydroxyapatite matrix protects enclosed DNA from...
Secondary Transfer
The movement of a glass fragment from a primary surface (which contacted the broken glass) to a secondary surface (which contacted the...
Touch DNA
Minute quantities of epithelial cells transferred by skin contact with a surface, without leaving a visible stain. Collected by swabbing contact points...

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