Abstract
Although the low-template or stochastic threshold is in widespread use and is typically set to 150–200 rfu peak height, there has been no consideration on its determination and meaning.
In this paper we propose a definition that is based upon the specific risk of wrongful
designation of a heterozygous genotype as a homozygote which could lead to a false
exclusion. Conversely, it is possible that a homozygote {a,a} could be designated as {a,F} where ‘F’ is a ‘wild card’, and this could lead to increased risk of false inclusion. To determine
these risk levels, we analysed an experimental dataset that exhibited extreme drop-out
using logistic regression. The derived probabilities are employed in a graphical model
to determine the relative risks of wrongful designations that may cause false inclusions
and exclusions. The methods described in this paper provide a preliminary solution
of risk evaluation for any DNA process that employs a stochastic threshold.
Keywords
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Article info
Publication history
Published online: January 21, 2009
Accepted:
November 3,
2008
Received in revised form:
September 10,
2008
Received:
March 12,
2008
Identification
Copyright
© 2008 Elsevier Ireland Ltd. Published by Elsevier Inc. All rights reserved.
