A Pioneer in Forensic DNA

Yes, I started in that particular laboratory 25 years ago, because at that time, the Dutch politicians introduced a new law which gave suspects, who were forced to donate a blood sample for forensic DNA research, were given the independent right for a contrast piece. So, there was a need for a contrast piece laboratory in Holland. So, the Ministry of Justice shopped around to all the universities, and Leiden University agreed to house the contrast piece university, and they asked me if I would like to become the head of that particular laboratory. So, I thought about a month or so and then I agreed.

In the beginning, it was not so much forensics, but it was population genetics, because I knew that doing forensics also meant that you had to invest in population genetics, in order to read the data. And, I very much like all the statistics involved in population genetics. But, in the end, also I like the technological developments, and if there is any field that in science that technology has played a major role, it’s DNA research, in the general sense. And my lab is part of a very big, technology driven, human genetics department. It was already 25 years ago, and it still is. So, I’m just exactly where I want to be.

Well I’m certainly one of the first people speaking about it, for already a long time now predicting in the end that it would become a major field, but as with all new technologies, especially forensics, many will fail to deliver, so you never know in advance if you start a new technology, whether it will be successful. But, as stubborn as I am, I think we can agree that it is now successful. So, we have an end product. We can do massively parallel sequencing in forensic casework very successfully. So, it took 10 years, but we do it now.

You know, that’s not a problem, because we can only use technologies which are ISO 17025 accredited. When the court reads that this technology is accredited in Holland, they know that it has underwent rigid testing and quality assurance testing, so they know that it is reliable and useful. Nevertheless, they also need to be able to understand exactly what you are doing, and the major advantage of applying massively parallel sequencing to STRs is that the court system is used to working with STR variation. We just identified the STR variation in a different way. So, it is very close to their comfort zone. That is the reason why I deliberately choose to stay using STRs as the first example of massively parallel sequencing, because it is close to what judges think they understand. And that helps tremendously. So, it wasn’t challenged. Also, not by the defense.

We will see a great change of laboratories using massively parallel sequencing in not necessarily routine technology, but in those stains where capillary simply fails to deliver results, where there is still enough DNA to be interrogated is where massively parallel sequencing can help you out. But I see the way we use massively parallel sequencing right now as an intermediate phase between capillary and just going for whole genome sequencing. Because I think that, in the end, is where we are going, but it is too far fetched for most people right now in forensics. Not in clinical diagnostics, but in forensics it is.

Years, at least.

Well, three things. The first, getting Y-STRs successfully used in forensics, which is what I did in the late 90’s together with Manfred Kayser and Lutz Roewer, and now it is a routine tool, but we were the first. And now, later, developing a DNA isolation method which allows me to get DNA profiles out of cartilage, which were at that time, considered to be impossible to get DNA profiles from, but we can, and we introduced the technology, and finally now it is seen that it is delivering – also in the United States. Labs took over the technology which I developed. And, massively parallel sequencing is still the nicest thing, because that’s something that where I was involved in not only the lab work, but also the idea space. So, writing the scripts. Writing the software. And also being able to demonstrate, even in court, if necessary, what you are doing. And then to even be able to show every single read you get out of an experiment. That is something that we thought about very carefully when we started with everything, and we now have a full product, and it’s being used now, at least in Holland. And it will be slowly used now in other countries. I think that it will have, in the end, a major impact.

It’s very simple. I will explain very, very simply what massively parallel sequencing for short tandem repeats is. Most people probably already know it, basically. And I will present three different case examples, where I will show the comparative value in using MPS in cases where capillary couldn’t deliver the essential message. Meaning you could either exclude a suspect or include a suspect or make a choice between two equally likely suspects. So, that’s exactly what you can do with MPS, so that’s what I will show.

The lion. As a predator, I think that the lion is the most unpredictable. I understand cats, but lions have the capability of hiding their emotions, whereas leopards and tigers can’t. So, I would feel more safe among the leopards or tigers than a lion.