Predicting Facial Morphology Using DNA Phenotyping

When trying to identify a perpetrator of a crime, phenotyping is another tool that investigators have to generate leads and narrow down suspects. Susan Walsh, Assistant Professor at IUPUI, describes what traits can currently be predicted based on DNA evidence and the direction she’s researching next. She also shares advice for others considering a career in forensics, and touches on the future of forensic science.


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Laura: Hi, we’re here today with Susan Walsh. Susan, why don’t you tell me a little bit about your background?


Susan: Sure. My name is Susan Walsh. I’m an Assistant Professor at IUPUI, Indiana University Purdue University Indianapolis. I do my research in forensic DNA phenotyping. My background is a masters in DNA profiling and a PhD in forensic genetics from the University of Erasmus in Rotterdam.


Laura: How did you get interested in phenotyping and the work that you’re doing now?


Susan: Well, we have a lot to do. So, I began with the idea during my masters. Actually, it was a funny story. I was intrigued by a paper that had just recently come out that was on twins. And it was investigating the quantitative traits of eye color, actually, in twins, and I thought that was fascinating that we could actually be able to predict what a person looks like from their genetic material. Because it made sense that you could, and then just that whole area was intriguing. And then a few years went by and I kind of always knew that I wanted to get back into that. I came across Manfred Kayser’s lab and I was happy enough that he took me back on and I got back in there.

It’s science fiction to a degree. There may be traits that we’ll never be able to predict quite accurately, or individualized prediction, but we can certainly do a good attempt and for pigmentation, it’s one of the easier traits to predict. Height is a little bit more difficult. There are a lot of environmental factors there, and now we’re seeing what’s possible with facial morphology.


Laura: It’s very interesting. I would assume facial morphology is very difficult because of all of the different points that you have.


Susan: It’s a complex traits. There are multiple processes that are enabling the formation of the face, and of course you’ve got differences between ethnicities, populations… So there’s a lot to factor in, but it’s really exciting.


Laura: it’s very exciting. I think you were on our future of forensic panel that we had this year at ISHI. What was that like? Was there any themes, trends? What does the future hold?


Susan: The future holds a lot if you don’t get ahead of yourself, right? So there has to be some type of regulation. Good scientific practice. And I that goes beyond my area of phenotyping. If we can put in the work into scientific publications, establishing protocols, standardization, then yeah, the future is bright.


Laura: That’s very exciting. You have an NIJ grant, and I’m not sure if you’re still working on that? Where does that stand?


Susan: So, I had a NIJ grant on pigmentation, and now I currently have an NIJ grant on facial morphology. So, I will always continue to work. So, you know, it’s great to get funding, and the support from NIJ has been phenomenal. We continue to do research on pigmentation, and now, with the additional of facial morphology, we have so much work to do.


Laura: That’s really exciting. How have you found the show so far?


Susan: Great! I like the interaction with the students. It’s great that they’re getting exposed to research as well as the practitioners stories about how these things are being applied. And that they can just walk up to any of the people there. Maybe the head honchos and just walk up and have a conversation with them. They may not get a chance to do that other places.


Laura: I really do love the openness and the way that people come together here.


Susan: It’s a great community!


Laura: It really is. What’s next for you?


Susan: Continue to do research. I have so much to do. It’s just so exciting to get up in the morning and be able to do this research. I’m very lucky and work with some great people.


Laura: Is there any advice you would give to somebody who’s thinking about a career like yours?


Susan: Perseverance, and there’s a bit of luck in there too. You can do anything you put your mind to. The doors opened up for me. It’s luck in a way, but I think that beyond top grades and everything, it’s passion. If you have passion for an area, you have passion for a topic, just go for it, and you will shine and people will see you. And that’s how you get into it.


Laura: That’s wonderful. Let’s also talk about practical applications and things you see in the media. Privacy concerns in that area?


Susan: So, luckily for us, phenotyping is an intelligence tool, and at the moment, it doesn’t have the capacity for individualized predictions. So, what we’re generating is group traits, such as do you have blue eyes or brown eyes? So, we’re not actually getting down to the level of individualized predictions or identity profiling, so we’re ok. It would be the equivalent of using CCTV cameras and pretty much that’s everywhere these days.


Laura: Thank you. Is there anything else about your work that we haven’t covered that you’d like to talk about?


Susan: No. I think, as I said, scientific validation is so important, and just if there’s any group or state lab or local lab that has any questions about phenotyping, please contact me. Contact Manfred Kayser. We are researchers, but we can’t do our job unless we speak with practitioners, and to actually speak with practitioners is ideal, because we’ll make something that they want to use and vis versa – they will use something that has been made for them. So, I think that communication is essential and I’d really like to promote that idea. Give me an email. Let us work together on a case – you may have a cold case in your lab. I think that generating a buzz about phenotyping, that it’s possible right now, especially for pigmentation, that’s something that I really want to kind of push and get the United States moving on phenotyping on cases.


Laura: That’s wonderful to be able to see everyone internationally come together here and share information in the larger sense.


Susan: Oh, absolutely. Yeah, we have to work together if we want to push the boundaries of science, right?


Laura: Well, Susan, thanks for coming in. We really appreciate it and I hope you come back.


Susan: Yeah, sure, absolutely.