4 Univ of Idaho Students Murdered - Bryan Kohberger Arrested - Moscow # 76

[Observant-ADHD-ENFP-BSc]

What should raise most eyebrows is that I remember reading that they immediately did a CODIS sample AND a STR or SNP test to speed up the genealogy process. Im not a forensic scientists but that sounds like they had more than just a tiny sample to work with…

MOO

RSBM
I love your whole post and wanted to respond to the bolded.
PCR is a polymerase chain reaction. It is a process that amplifies and replicates the target DNA sequence so that it can be used for other tests. I know from experience that this is one of the first processes used when handling a DNA sample; this is one of the tests to know if you have a viable sample.
I'm impressed, to be honest. I understand the DNA part, but how they got the sample from the inside opening of the button is beyond me, I did grow some pretty nasty stuff from swabbing the elevator button and growing it in a dish for a few weeks. So gross.
JME (Recent biotechnology grad)

 

[gliving]

@schooling This might be of interest : )

https://isp.idaho.gov/forensics/wp-content/uploads/sites/10/documents/notices/2021_07_28_Molecular_Genealogy_Notification.pdf

To: Idaho Chiefs, Sheriffs, and Prosecutors
From: Matthew Gamette, ISP Forensic Services Laboratory System Director Subject: Cold Case Help--Molecular Genealogy Resources
Date: July 28, 2021

The Idaho State Police Forensic Services Laboratory (ISPFS) is extremely excited to announce that we have secured a Bureau of Justice Assistance grant to fund genetic genealogy testing and searching of unsolved Idaho cases. The cases we are starting with are unsolved homicide, sexual assault, and missing person/unidentified remains cases. Idaho is the first state in the country to take the state-wide approach for this technology. Instead of each law enforcement (LE) agency having to negotiate their own contract, pricing, and quality control with a private lab and genealogist, ISPFS has done that at the state level through the Idaho Department of Purchasing. In addition, by ISPFS securing federal grant funding, we can offer these services to local, county, and state agencies at no cost to the local LE agency. In order to facilitate this, ISPFS has formed a State Genetic Genealogy Investigation team consisting of laboratory personnel, an Idaho State Police investigator/detective, and a representative from the Rocky Mountain Information Network (RMIN) to identify cases eligible for testing under this grant. Once a case is identified as eligible, the team is reaching out to the local law enforcement agency and prosecutor to bring them onto the team for that case. The state team is a resource for local LE. Idaho now has a formal contract with Othram Laboratories (a prominent leader in forensic genealogy) to conduct the genealogy testing and forensic genealogy searching. ISPFS is ensuring that Othram follows accepted laboratory processes and procedures, and complies with the United States DOJ interim policy on Forensic Genetic Genealogy DNA Analysis and Searching.

ISPFS has already searched our records for cases we know would be eligible under this program. We have started contacting individual Idaho law enforcement entities and prosecutors on approximately 15 of those cases. The law enforcement entity and prosecuting attorney are being asked to confirm certain case criteria and sign an MOU that they will investigate this case if the molecular genealogy technique generates investigative leads, that they will follow DOJ policy for investigating these cases, and that they will take all appropriate prosecution actions as an outcome of the investigation.

We want to be very clear that the local or county law enforcement agency will retain jurisdiction and responsibility for the case. The state team is in place to identify cases, coordinate with local entities, provide investigation resources (if requested), safeguard that the molecular genealogy technology and techniques are being appropriately used in Idaho, and ensure that all necessary resources are reliable and available at no cost to local LE for use of this technique. ISPFS is committed to ensuring that the lab science and genealogy work is robust, that the evidence is treated appropriately by the contract lab and in a way that allows for appropriate prosecution, and that the contract with the private lab and federal funding are spent appropriately. If more funding resources are needed to support this effort, ISPFS will obtain those resources in support of all Idaho law enforcement. ISPFS is also evaluating offering these services in Idaho if the need is demonstrated from this project.

We are accepting requests to work other cases that have not been identified by our team. If you have those cases, please reach out to our appointed project lead on this effort Ms. Rylene Nowlin. She can be reached at 208-884- 7148 or Rylene.Nowlin@isp.idaho.gov All cases accepted into this program are subject to an MOU.

 

[Nichevo]

IMO genetic genealogy quickly found someone in BKs family tree. Since they were already honing in on him as a suspect it sped up the process. As they could simultaneously go up (BK’s name & dob & social) and down (the sheath dna sample) a known family tree.

In most of these genetic genealogy cases it takes months and months of research as most of them end with someone who was never on LE radar. Requiring LE to essentially build an entire family tree from scratch to find a potential suspect hidden within that fits location, age, background etc. Potentially hundreds of hours of research.

Once BK was in PA, Dad’s DNA was essentially a paternity test against their sheath sample ala the Maury Povich show. “You are the father!”

1. CODIS - no hit
2. STR/SNP + research they couldn’t exclude BK
3. Paternity DNA test on Dad and Sheath sample
4. DNA test on BK against the sheath sample confirming 100% match (IMO).

1&2 were done at the same time.

This is not the article I read last year, but it talks about the possibility of STR

Here's how DNA evidence is used in violent crime investigations

Experts say DNA evidence is an important piece of the puzzle, but it's not the whole puzzle.

www.king5.com

I’ve never heard any legitimate claim to the dna being challenged because of this. And that’s probably because this is the only community I participate in.

What should raise most eyebrows is that I remember reading that they immediately did a CODIS sample AND a STR or SNP test to speed up the genealogy process. Im not a forensic scientists but that sounds like they had more than just a tiny sample to work with…

MOO

I agree with most of your opinions, but I am not sold on forensic genealogy being instrumental for the reasons I listed above MOO.

I also agree that there may have been more than a “tiny sample” of DNA. However, with PCR, the size of the sample is essentially irrelevant, IMO.

PCR- a DNA copy machine

Kary Mullis, an American scientist, invented this procedure in his research in 1983 that was one of the greatest significant achievements in molecular biology. PCR revolutionized DNA research to the point that its inventor received the Nobel prize in Chemistry in 1993.

More specific to forensics is this article:

How Are Crimes Solved by PCR?

The body of a woman is found behind an abandoned warehouse on the outskirts of town. Forensic experts carry out a technical examination of the scene and

bitesizebio.com

Oops, I believe @Observant-ADHD-ENFP-BSc posted on PCR as I was busy composing this post, thanks Observant.

 

[schooling]

RSBM
I love your whole post and wanted to respond to the bolded.
PCR is a polymerase chain reaction. It is a process that amplifies and replicates the target DNA sequence so that it can be used for other tests. I know from experience that this is one of the first processes used when handling a DNA sample; this is one of the tests to know if you have a viable sample.
I'm impressed, to be honest. I understand the DNA part, but how they got the sample from the inside opening of the button is beyond me, I did grow some pretty nasty stuff from swabbing the elevator button and growing it in a dish for a few weeks. So gross.
JME (Recent biotechnology grad)

Thanks for the compliment and for the tidbit on that amplification process. I’ve always wondered why they are able to do this in some cases but not others. I remember seeing a dateline episode not too long ago where LE was left with only enough sample to do one more search and they were waiting for technology to improve. I believe it might have been incomplete or degraded.

Does that prevent the amplification process? In what situations does LE “run out of a sample(s)?”

If you’re not qualified to answer per WS rules then even your opinion would be valuable!

 

[schooling]

@schooling This might be of interest : )

https://isp.idaho.gov/forensics/wp-content/uploads/sites/10/documents/notices/2021_07_28_Molecular_Genealogy_Notification.pdf

To: Idaho Chiefs, Sheriffs, and Prosecutors
From: Matthew Gamette, ISP Forensic Services Laboratory System Director Subject: Cold Case Help--Molecular Genealogy Resources
Date: July 28, 2021

The Idaho State Police Forensic Services Laboratory (ISPFS) is extremely excited to announce that we have secured a Bureau of Justice Assistance grant to fund genetic genealogy testing and searching of unsolved Idaho cases. The cases we are starting with are unsolved homicide, sexual assault, and missing person/unidentified remains cases. Idaho is the first state in the country to take the state-wide approach for this technology. Instead of each law enforcement (LE) agency having to negotiate their own contract, pricing, and quality control with a private lab and genealogist, ISPFS has done that at the state level through the Idaho Department of Purchasing. In addition, by ISPFS securing federal grant funding, we can offer these services to local, county, and state agencies at no cost to the local LE agency. In order to facilitate this, ISPFS has formed a State Genetic Genealogy Investigation team consisting of laboratory personnel, an Idaho State Police investigator/detective, and a representative from the Rocky Mountain Information Network (RMIN) to identify cases eligible for testing under this grant. Once a case is identified as eligible, the team is reaching out to the local law enforcement agency and prosecutor to bring them onto the team for that case. The state team is a resource for local LE. Idaho now has a formal contract with Othram Laboratories (a prominent leader in forensic genealogy) to conduct the genealogy testing and forensic genealogy searching. ISPFS is ensuring that Othram follows accepted laboratory processes and procedures, and complies with the United States DOJ interim policy on Forensic Genetic Genealogy DNA Analysis and Searching.

ISPFS has already searched our records for cases we know would be eligible under this program. We have started contacting individual Idaho law enforcement entities and prosecutors on approximately 15 of those cases. The law enforcement entity and prosecuting attorney are being asked to confirm certain case criteria and sign an MOU that they will investigate this case if the molecular genealogy technique generates investigative leads, that they will follow DOJ policy for investigating these cases, and that they will take all appropriate prosecution actions as an outcome of the investigation.

We want to be very clear that the local or county law enforcement agency will retain jurisdiction and responsibility for the case. The state team is in place to identify cases, coordinate with local entities, provide investigation resources (if requested), safeguard that the molecular genealogy technology and techniques are being appropriately used in Idaho, and ensure that all necessary resources are reliable and available at no cost to local LE for use of this technique. ISPFS is committed to ensuring that the lab science and genealogy work is robust, that the evidence is treated appropriately by the contract lab and in a way that allows for appropriate prosecution, and that the contract with the private lab and federal funding are spent appropriately. If more funding resources are needed to support this effort, ISPFS will obtain those resources in support of all Idaho law enforcement. ISPFS is also evaluating offering these services in Idaho if the need is demonstrated from this project.

We are accepting requests to work other cases that have not been identified by our team. If you have those cases, please reach out to our appointed project lead on this effort Ms. Rylene Nowlin. She can be reached at 208-884- 7148 or Rylene.Nowlin@isp.idaho.gov All cases accepted into this program are subject to an MOU.

Oh wow! They were probably super excited to get work on this case and to get a hit so quickly.

I remember reading early on in this investigation that this might have been the first time they started processing their sample for genealogy and codis.

 

[Observant-ADHD-ENFP-BSc]

Thanks for the compliment and for the tidbit on that amplification process. I’ve always wondered why they are able to do this in some cases but not others. I remember seeing a dateline episode not too long ago where LE was left with only enough sample to do one more search and they were waiting for technology to improve. I believe it might have been incomplete or degraded.

Does that prevent the amplification process? In what situations does LE “run out of a sample(s)?”

If you’re not qualified to answer per WS rules then even your opinion would be valuable!

JMO
Incomplete or degraded would cause problems in the PCR. It would just keep coming back as failed. The tech is evolving so fast, that what I used last in 2020 (I was a lockdown grad ), could likely already be upgraded.
The target dna is just a snippet of the whole thing, but it is a sequence, for example, like a flush in poker, it cannot be a flush if you don't have the correct sequence. If for any reason the complete target dna sequence is not there, then you do not have a 'flush', but you can try again. This is where the quantity of the sample could be diminished, just by attempts to PCR. You only need one successful PCR, but you could run out if a sample is degraded or fragmented enough.
(I actually isolated a piece of parsley's DNA, and replicated it, and later, ran several DNA fingerprinting tests for a 'Suspect', completely hypothetical, the components are set up for education, I didn't handle any real suspect dna)
ETA: a little clarification and a mini experience)

 

[schooling]

I agree with most of your opinions, but I am not sold on forensic genealogy being instrumental for the reasons I listed above MOO.

I also agree that there may have been more than a “tiny sample” of DNA. However, with PCR, the size of the sample is essentially irrelevant, IMO.

PCR- a DNA copy machine

Kary Mullis, an American scientist, invented this procedure in his research in 1983 that was one of the greatest significant achievements in molecular biology. PCR revolutionized DNA research to the point that its inventor received the Nobel prize in Chemistry in 1993.

More specific to forensics is this article:

How Are Crimes Solved by PCR?

The body of a woman is found behind an abandoned warehouse on the outskirts of town. Forensic experts carry out a technical examination of the scene and

bitesizebio.com

Thanks for the link on PCR. I’m in technology and always associate dna with bytes and always wondered why it couldn’t be replicated. This explains it all.

I think they had enough to send a team out to that trash can even without the genealogy. The only reason I entertain it is because the use of Forensic genealogy was widely reported at the time and attributed to sources (I know that doesn’t mean much nowadays) within LE.

I think the reason they could move so
quickly is that they had a known suspect with a known family tree. That dramatically reduced the time needed and the potential suspect pool.

Also, there wasn’t a direct hit on BK because he likely used a paid service and stopped there. Most paid services (Ancestry.com etc) have only complied with LE a few times in their decades of existence. In which they claimed that they were duped. Not finding BK in a free database is only evidence of him choosing not to go that route. Not evidence that LE didn’t utilize them.

My sister submitted her DNA to Ancestry but did not utilize any of the open databases after the fact. So her DNA would not be in the latter. So forensic genealogists might find a family member in there but they won’t find my sister.

 

[schooling]

JMO
Incomplete or degraded would cause problems in the PCR. It would just keep coming back as failed. The tech is evolving so fast, that what I used last in 2020 (I was a lockdown grad ), could likely already be upgraded.
The target dna is just a snippet of the whole thing, but it is a sequence, for example, like a flush in poker, it cannot be a flush if you don't have the correct sequence. If for any reason the complete target dna sequence is not there, then you do not have a 'flush', but you can try again. This is where the quantity of the sample could be diminished, just by attempts to PCR. You only need one successful PCR, but if a sample is degraded or fragmented enough, you could run out.

Much appreciated! It’s always been one of those things where no amount of Google searches and keyword combinations could give me a direct answer and published papers were far too complex.

This was perfect!

 

[Nichevo]

Thanks for the link on PCR. I’m in technology and always associate dna with bytes and always wondered why it couldn’t be replicated. This explains it all.

I think they had enough to send a team out to that trash can even without the genealogy. The only reason I entertain it is because the use of Forensic genealogy was widely reported at the time and attributed to sources (I know that doesn’t mean much nowadays) within LE.

I think the reason they could move so
quickly is that they had a known suspect with a known family tree. That dramatically reduced the time needed and the potential suspect pool.

Also, there wasn’t a direct hit on BK because he likely used a paid service and stopped there. Most paid services (Ancestry.com etc) have only complied with LE a few times in their decades of existence. In which they claimed that they were duped. Not finding BK in a free database is only evidence of him choosing not to go that route. Not evidence that LE didn’t utilize them.

My sister submitted her DNA to Ancestry but did not utilize any of the open databases after the fact. So her DNA would not be in the latter. So forensic genealogists might find a family member in there but they won’t find my sister.

“Thanks for the link on PCR. I’m in technology and always associate dna with bytes and always wondered why it couldn’t be replicated. This explains it all.“ - IMO that is a very apt comparison.

My undergrad degree was in biology with a chemistry minor, but I am a little embarrassed to admit that PCR was in its infancy when I graduated .

 

[Observant-ADHD-ENFP-BSc]

Much appreciated! It’s always been one of those things where no amount of Google searches and keyword combinations could give me a direct answer and published papers were far too complex.

This was perfect!

The papers are brain-melting, but I must confess the professors that taught me were mostly excellent teachers and extremely passionate about the subject and education. If I am allowed (admins please snip if not allowed), I would recommend Khan Academy for understandable summaries, especially for Math and Chemistry.

 

[Observant-ADHD-ENFP-BSc]

Thanks for the link on PCR. I’m in technology and always associate dna with bytes and always wondered why it couldn’t be replicated. This explains it all.

I think they had enough to send a team out to that trash can even without the genealogy. The only reason I entertain it is because the use of Forensic genealogy was widely reported at the time and attributed to sources (I know that doesn’t mean much nowadays) within LE.

I think the reason they could move so
quickly is that they had a known suspect with a known family tree. That dramatically reduced the time needed and the potential suspect pool.

Also, there wasn’t a direct hit on BK because he likely used a paid service and stopped there. Most paid services (Ancestry.com etc) have only complied with LE a few times in their decades of existence. In which they claimed that they were duped. Not finding BK in a free database is only evidence of him choosing not to go that route. Not evidence that LE didn’t utilize them.

My sister submitted her DNA to Ancestry but did not utilize any of the open databases after the fact. So her DNA would not be in the latter. So forensic genealogists might find a family member in there but they won’t find my sister.

RBBM
Exactly. I think they utilised what they could from open to public digital records first after CODIS failed, possibly hitting brick walls, with private data. Still, there are people who are hired and paid extremely well genealogists, who can get as close as possible to their suspect. Still, normally in their profession, they would be looking for a family connection from Johnny LE (Customer) to Matty Sus (Unknown ancestor).
GEDcom has the availability to the police, I dont recall if it is required to sign up or if it is an option. There was a discussion a while back at the beginning of the year about which DNA sites gave LE access and which did not, and which were opt-in from the customer or not.

 

[Emerald1328]

Welcome to Websleuths, @CrimeKitty29 !

I think the perpetrator thought about killing for a very long time, and studying crime was a way to explore and facilitate that. I think he had a fantasy, and he carried it out. I think the knife was important, that using the knife to kill was what he thought about for so long. We have no indications of sexual assault, so though I think this did have sexual elements, he gained satisfaction from the act of stabbing, not conventional rape. I think he stalked the house, but I don't necessary think he had a fixation on one person; it would have been virtually impossible for him to know who - if any - of the housemates was at home (and he wouldn't have recognised Kaylee's new car at all), since he didn't watch the house for hours on the night in question - he drove up, killed, then left. Any of the housemates could have still been out at a bar or club or frat/sorority house, or crashing on a friend's sofa. He also would have found it virtually impossible to tell the housemates apart in the dark, especially Maddie and Kaylee who bore a sisterly resemblance and were asleep in the same bed. I think he's arrogant, and convinced of his own intelligence and cleverness, so he made a lot of really basic mistakes. He assumed he was smarter than the police and other law enforcement assigned to the case would be, and, as a result, he was in custody in under two months. He lacked the insight that he needed to be more covert, to see that actions like using his own car, to taking his phone on his preliminary stalking missions, turning his phone off when actually committing the murder, and so on, actually highlighted him as a suspect.

But yeah, we will probably learn more in the future, and my concept of the crime and the person who did it will shift and change accordingly, but that's where I'm at right now.

MOO

I agree with every single bit of this. I have followed this case from the very beginning. I posted quite frequently in the beginning but haven’t posted for awhile for various reasons. Fantastic post.

 

[Justice101]

I probably only know 0.1% of what I need to know about PCR but I find it very fascinating!

I wondered how they can create many many copies of the same DNA strand.

 

[10ofRods]

RSBM
I love your whole post and wanted to respond to the bolded.
PCR is a polymerase chain reaction. It is a process that amplifies and replicates the target DNA sequence so that it can be used for other tests. I know from experience that this is one of the first processes used when handling a DNA sample; this is one of the tests to know if you have a viable sample.
I'm impressed, to be honest. I understand the DNA part, but how they got the sample from the inside opening of the button is beyond me, I did grow some pretty nasty stuff from swabbing the elevator button and growing it in a dish for a few weeks. So gross.
JME (Recent biotechnology grad)

Nothing needs to be grown from the snap on the sheath, though. DNA is so small that it persists in any nook or crevice (including microscopic nooks and crevices). We find it everywhere and in this case, they found a good sample (enough to match to a human person). Not every single base pair needs to be present, but often, all of them are (I would expect them to be so, in this case). Then yes, PCR amplifies that for study.

Anthropologists have recovered DNA from almost anything you can think of. New methods are emerging to source the last "home" of the DNA (in this case, it would be an epithelial/skin cell) so that we can tell whether the DNA was transported to where we found it by dust or rain or air:

https://journals.asm.org/doi/full/10.1128/AEM.01504-19

The amount of DNA a person breathes out with each breath (epithelial DNA again) is small, but can be documented. I am hopeful that somewhere in the air filter system for the house or in the depths of those forensic vacuums they said they used at 1122 King, there will be more of BK's DNA.

I am also hopeful that at least some victim DNA will be in the car (tiny amounts on the car mat). Washing things doesn't work as well as most criminals think; we use something other than laundry detergent or bleach to destroy DNA on outer surfaces of bones and teeth, when we think there's going to be DNA in the marrow chambers or inside the tooth. I am not going to say what that chemical is, though!

It's not household bleach.

IMO. DNA is either there or it isn't. If the completely (non-junk) DNA sequence of a particular individual is on a use point (the snap) there are likely many epithelial cells there, in various states of degradation. But DNA does not degrade the way the cell membrane does, or the nuclear membrane does. It's quite persistent. The four bases persist on objects that have traveled long distances through space:

Meteorites could have brought DNA precursors to Earth

Analyses of three meteorites suggest that the raw material for the origin of life may have formed in space.

www.nhm.ac.uk

Of course those weren't assembled into strands or chromosomes. Quite a bit of mammoth DNA, but then they found something even older (2 million years of persistence):

The world's oldest DNA represents a two-million-year-old ecosystem

DNA found in Greenland has broken the record for the oldest yet discovered.

www.nhm.ac.uk

A near term event like the murders in Moscow should have plenty of DNA connected to it, and I'm sure LE has samples from all roommates, BK, and many other people with which to compare what they found on the sheath. It matched BK.

(Finding blood in his car, even if it's his own, with DNA) would still be an interesting find. I keep trying to picture him rapidly taking off his second pair of gloves (without touching the other pair) or removing two pair (without touching the new pair with bloody hands). Hard to do. I do think he had bloody hands. He may think his compulsive cleaning did the trick - but I myself doubt it very much.

IMO.

 

[Justice101]

10 of Rods....

I am curious. If BK washed some of the victims blood off in his sink, would that DNA that stuck to the inside of the pipe be useable? Also, how about blood that WICKED INTO the car seat fibers.. Not on the surface, but in the fibers perhaps even rubbed with 100% sodium hypochlorite (in other words not Clorox which is only 50%).

 

[gliving]

Can DNA still be present after going through a washer and dryer cycle? tia

 

[10ofRods]

Thanks.

I don't know why there was a discussion about the DNA not being a part of the probable cause.

Wait, it had to do with the judge saying it wasn't going to be counted as part of the probable cause.
I assume because it has to be proven to be BK's by an expert.

If you or anyone can find this information by the judge I'd appreciate it. Seems a bit confusing that it is in the PCA yet not being considered for searches and arrest, yet it is the DNA that led to BK being the top suspect.

I think the judge in Idaho contemplated the entire PCA.

Then they wrote a new one for the PA search warrant, and in that one, they made the DNA a kind of footnote (or something - they did not emphasize it).

Someone will remember more than I. But it's definitely in the original Idaho PCA. There's also a WA search warrant, don't know if it mentions DNA or not or even if we've seen it.

IMO.

The probable cause discussion about the DNA in PA took place because they wanted the search warrant to still stand, even if the DNA they were about to acquire was problematic (apparently, it wasn't).

IMO.

 

[10ofRods]

10 of Rods....

I am curious. If BK washed some of the victims blood off in his sink, would that DNA that stuck to the inside of the pipe be useable? Also, how about blood that WICKED INTO the car seat fibers.. Not on the surface, but in the fibers perhaps even rubbed with 100% sodium hypochlorite (in other words not Clorox which is only 50%).

Yes, it would. It had been awhile since he would have done that, but I would think they'd have brought in sink swabs, just in case. My big puzzlement is how he got his bloody gloves off and disposed of them without getting blood on his actual hands (he's not four-handed). And he would certainly have washed his hands many times over days, after getting home. However, the fact that he wore gloves (we think) during the crime would certain play a big role in diminishing sink DNA.

Car seat fibers would be very hard to thoroughly clean (as one cannot get to the underside of them easily). Bleaching can destroy DNA, but it usually takes many bleachings to get rid of it (and that would be very obvious to investigators and it would have been obvious to BK's dad as well). Bleach + surfactant can remove detectable DNA after 10-12 launderings, sometimes fewer. But that means putting the item in a washing machine, agitating it, and using both detergent and bleach - many times.

The seat belt is a very promising thing to study, especially as the component that buckles has grooves and microscopic wear and tear that would hold blood-based DNA fairly well. I assume he took off his killer-gloves and put on new gloves, though, before getting in the car (or did he? he was in a big hurry by then, it seems - he had his shoes, coveralls and hands to worry about).

As you all can probably tell, I"m on the edge of my seat until June. I've never followed a case where I believed the murderer took such care about blood and DNA, so I want to know how "successful" he really was. I'm thinking he was pret' darned successful, but DNA is 1) hard to destroy and 2) invisible. We know there was some on the bottom of one foot, at least - but how far it went to create a DNA trail inside the car, we do not know.

He would have had blood on his hands, probably also the ends of his sleeves, and on his feet. He had to deal with all of that before getting (quickly) into the car, which he would not have had to do if his plan had gone according to his own fantasy of it (IMO, of course). Xana's words and what DM heard mean that BK knew he might be encountering police soon (he wouldn't have known that DM didn't call right away).

IMO.

 

[10ofRods]

“Thanks for the link on PCR. I’m in technology and always associate dna with bytes and always wondered why it couldn’t be replicated. This explains it all.“ - IMO that is a very apt comparison.

My undergrad degree was in biology with a chemistry minor, but I am a little embarrassed to admit that PCR was in its infancy when I graduated .

It was invented the year I got my doctorate; Kary Mullis was just 41, IIRC, when he and one other person figured it out. He shared the Nobel Prize for it in 1993.

I remember my genetics prof saying that we wouldn't have the addresses of the human genome until around the year 2000, but the companies hired to work on it came in with the data way faster, in part due to Mullis's discovery of PCR in 1985.

The whole landscape of crime was to change - for good, I think.

IMO.

 

[10ofRods]

Can DNA still be present after going through a washer and dryer cycle? tia

Absolutely. Heat and cold have no effect on DNA.

However, repeated thorough washing even of items rich in DNA (like underwear) shows that DNA can persist through many launderings.

Persistence of DNA from laundered semen stains: Implications for child sex trafficking cases

In sexual assault cases, particularly those involving internal child sex trafficking (ICST), victims often hide their semen-stained clothing. This can…

www.sciencedirect.com

The above study used a rich source of DNA (semen) and cotton (better preserver than polyester, apparently, but polyester still preserves DNA). Multiple washings over time still allowed DNA to be detected in laundry water and on other clothing washed with the DNA-imbued item.

Nylon preserves the least:

https://www.tandfonline.com/doi/abs/10.1080/00085030.2003.10757551

Did BK know this? I can't wait to find out.

IMO.