10/28/2024 — Andrea Burkhart recap

https://www.youtube.com/live/7l716sqd8mU?si=T5RbQnSNVSTK7xRo 

Question 1, what types of quality control are necessary in testing for DNA reagents?

We didn't hear anything about DNA reagents in direct or cross examination. This is not a subject. Somebody on the jury brought that in. She said that essentially they prepare them with their own chemical components so they know what the components are. They log the dates and times when reagents are prepared, and they also use positive and negative controls to make sure that they get expected results.

Question 2. Do you need to do repetitive testing to validate results?

She says, no, we don't reproduce it. It's part of the validation process in the lab to determine if they get consistent results. So they make sure the process yields reproducible results.

If the sensitivity level doesn't produce sensitive results, then they will. That will affect how they set the standard. This is talking about that quantification level, at what point they determine they have enough to be able to create results that can be replicated below that level. It's too inconsistent, it's too unpredictable whether they will replicate it. So that determines where they set that standard for quantification.

Question 3, Do multiple people perform various phases of the analysis?

She says, not in their lab. There is one analyst to one case. Sometimes there's only a serological examiner and a separate DNA analyst, but not most of the time. She did not have any consistent assistant or another analyst that helped her in this case.

Another question, sophisticated understanding:

Question 4, How do you handle chimeras?

Chimera is not mentioned anywhere in this examination. Somebody has a very sophisticated understanding of DNA. Chimera is when one person produces multiple DNA profiles. There can be a variety of reasons of this. Some of this is developmental or not developmental, but just inherited, like genetic types of conditions.

Another one has to do with transfusion or if there's been a like transplant, something like that. She even comments, that's a really good question. So she says individuals have unique. Individuals can have a profile where their, their, their body fluids may have different profile profiles. She says she's never run into it.

If it, if it happened, they'd have to consider if it is an expected result. In other words, who do you think the sample is from? And are you predict this person might have a achmeric type of sample, otherwise it would probably really, really confuse them. She says they do ask if the individual has been transfused when they are getting their standards, because that person could potentially exhibit two profiles. And in that case they would need a full profile from both individuals, the transfusion donor and the recipient as well.

Question 5, are your storage refrigerators for samples locked at all times, even if they are in the locked lab? 

She says no, she has. They have like lockers, kind of storage boxes that they use to hold their work while they're working on it and typically is locked if it has samples in it. However, they do consider the lab secure, so they do not always lock their little boxes. The fridge, however, is always locked.

Question 6, What restricted access policies were in place?

She says it requires a badge to get into the lab, and only biological analysts can get into that area of the lab unattended. If there were analysts from other units, they would have to be escorted in. There's only a couple of entry points into the lab for people who are contributing items. If they're going to go anywhere beyond that point, they also have to be escorted.

So clearly the. The jury is concerned here about the potential for contamination and potentially unlawful access. They are. They are. They're asking questions that suggest they're having these types of questions about whether there might have been some kind of problem, some kind of problem with the access into the lab.

8

That is, is quite remarkable to me.

Question 7, Can toxic drugs or inhalants alter DNA strands?

This is the point where I wrote in my margin, someone is hella informed. She said she is not sure. There are some drugs that can affect the morphology of cells, meaning basically just the cell shape, sperm cells in particular, she called out as being able to be affected by certain drugs. She says she does not know whether that would affect whether DNA would be left behind or not.

So now we're getting back to that. These swabs with the presumptive positive for seminal fluid, but no male DNA detected. Really as close as they got to ever saying the word vasectomy. Didn't say the word vasectomy because we're talking about drugs and that other situation.

Question 8, Final question, what is PCR?

When she described the amplification process, she just used the acronym pcr. So here she explains, it's polymerase chain reaction. It's how they make all of the copies in order to visualize the sample that they receive.

That's what we got from Stacy Bosnowski.