Colonelhall,
You may find PMF a plausible bunch, but I find that this site has much misinformation on DNA forensics. At this site an
anonymous commenter wrote, “[Rose Montague] claimed that Sollecito's DNA on Meredith's bra clasp was LCN DNA despite the fact that the lowest RFU peak was 30% higher than that the 50 RFU test widely used for minimum reliability and the highest RFU peak was more than 200% higher.” The anonymous commenter, The Machine, said this disparagingly, but it is she who is wrong.
One, LCN DNA is defined either in terms of amount of template DNA, such as 200 picograms, or it is defined as the point where stochastic effects begin to manifest themselves. It makes no sense to define the LCN range in terms of peak heights in RFUs because one could alter a sample from being in the LCN range to outside of the LCN range just by doing more PCR cycles. Doing more cycles would not change the amount of template DNA and would not make the stochastic effects go away.
Two, if The Machine believes that 50 RFU is the appropriate standard for minimum reliability, then she needs to explain why the knife DNA profile is acceptable. 22 of 29 peaks fall below this intensity threshold. This is one of several good reasons to toss this particular piece of evidence, in my opinion.