UC Santa Cruz alumna Cristina Valencia earned her Ph.D. in Anthropology in 2020 and is now the lab director for Astrea Forensics, a forensic service lab that applies state-of-the art and patented ancient DNA techniques and direct genome sequencing to identify human remains. The company’s mission is to solve cold cases, determining the identities of unknown people from samples that are too degraded for traditional forensics testing.
The UC Santa Cruz news team spoke with Valencia to learn more about her work and how her experience at UCSC helped to prepare her.
Q: How would you describe the work you do and the greatest challenges and rewards?
A: It is interesting but complex to be constantly confronted with the worst of what humans can do to each other. The challenge of this line of work is talking to detectives every day and hearing the last moments of someone’s life. It is often violent and lonely. However, the reward is the social good that this type of work puts out into the world. Half of our cases are unidentified individuals. We get to answer the question of who they are and bring closure to their family. And when we’re able to identify violent offenders and provide that information to law enforcement, that brings another level of closure.
Q: How is Astrea Forensics able to solve cases that were previously unsolvable?
A: One major technique we use is obtaining DNA from rootless hair, which was not thought to be possible for a long time. In the past, these types of hair samples were saved but did not provide additional information to cases. We are also now able to apply genotyping and genealogy to forensics. Our software allows us to make comparisons between a sample of unknown origins and a genotype file from a known individual, and that’s how we’re able to tie a sample from a crime scene to a particular suspect, once law enforcement obtains data from that person.
These techniques were pioneered by Richard Green, Astrea Forensics’ co-founder and scientific advisor, who is a professor of biomolecular engineering and bioinformatics at UC Santa Cruz.
Q: What perspective, skills, or experience have you brought into your work from your Ph.D. in anthropology?
A: All of the methods that we use are really cutting-edge, so I do my best to operate as ethically as we can, given the sensitivity of the data we generate. I see every sample as a person and strive to treat them with respect. I also think a lot about the implications of our science for stakeholders. And I work to create trust among our clients who want to understand our technology. This is all perspective that comes directly from my training as an anthropologist.
The forensic work I completed with Allison Galloway gave me a frame of mind to approach forensic thinking, including knowing what considerations you should make in the process of handling sensitive materials. Because of my training, I know the human skeleton well. I can evaluate remains in terms of sample quality and preservation, and I know what parts of the body are best to target for DNA. I originally came to Astrea Forensics because of my skills with ancient DNA, which I obtained from working with Professor Lars Fehren‑Schmitz. The skills that I applied to my dissertation became directly transferable to the work I do now.
Q: What made you want to choose the UCSC anthropology program, and what was your experience like?
A: I had a good experience going through this program. While it was difficult, I was able to get the support I needed from my advisor. My advisors also encouraged me to attend events with other people in the department, which broadened my thinking about the world, my place in it, and the role of science.
Q: Do you have any advice for current students as they chart their paths to future careers?
A: Think outside of the box about how your skills apply to different contexts. I knew I could do parts of this job, like extractions and library preparation, but I was a bit nervous initially about how I would fit in within the field of biotech, since my background is in social sciences.
I’ve found that skills I learned through my Ph.D. allowed me to think critically about what we are doing and how we do it. It also allowed me to learn to manage my workload, juggling different cases in different phases of the pipeline and connecting the data. After graduating, I had to think about the skills I learned in managing research projects and data and how I could apply them outside of the classroom. Be creative about what you can do with your skills, and be flexible about pursuing career opportunities, even those that may not be what you initially had in mind.