Above: Forensic scientist at work (photo courtesy gettyimages, D-Keine)
Social Sciences Q&A with Cristina Valencia
For Cristina Valencia, every strand of DNA tells a story—sometimes, it’s a story long buried, waiting to be uncovered. As the lab director for Astrea Forensics, the UC Santa Cruz alumna applies groundbreaking ancient DNA techniques and direct genome sequencing to bring identities to the nameless and resolution to families who have waited decades for answers.
With an M.A. (’15) and Ph.D. (’20) in anthropology from UCSC, Valencia navigates the intersection of cutting-edge science and human history, solving cold cases once deemed unsolvable. It’s a career that requires both technical precision and deep compassion, as she works with law enforcement and forensic experts to illuminate the past and seek justice for those lost in its shadows.
Cristina Valencia (M.A.’15; Ph.D. ’20, anthropology)
“It is interesting but complex to be constantly confronted with the worst of what humans can do to each other,” Valencia said. “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.”
Her team specializes in extracting DNA from rootless hair—previously thought impossible until UCSC Professor of Biomolecular Engineering Ed Green developed a technique to do it—and applying genotyping and forensic genealogy to identify unknown individuals. By comparing DNA samples to known genotype files, they help law enforcement link evidence to suspects. Valencia’s anthropology background informs her ethical approach, ensuring each case is handled with care and respect.
Valencia credits work she did with UCSC Professors of Anthropology Alison Galloway and Lars Fehren-Schmitz for giving her the cutting-edge skills to solve these cases with Astrea Forensics.
“The forensic work I completed with Alison 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,” Valencia said. “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.”
While pursuing her Ph.D., Valencia focused on the analysis of ancient Mayan skeletal material using paleogenomic and osteological approaches in her investigation of the practice of human sacrifice. Her training is primarily in human osteology, archaeology, population genetics, and bioinformatics.
Valencia says that the skills she learned through her Ph.D. allowed her to think critically about forensic work and its processes. They also helped her develop the ability to manage her workload, juggle multiple cases at different stages, and connect complex data.
For current students at UCSC, Valencia emphasizes “thinking outside of the box about how your skills apply to different contexts.” She says that it is important for students to recognize their transferable skills, even if their background differs from their intended field. She recalled that while she was confident in tasks like extractions and library preparation, she initially felt uncertain about fitting into biotech due to her social sciences background.
“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,” Valencia said. “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.”
As she continues her work at Astrea Forensics, Valencia applies those same principles, using cutting-edge science to uncover identities, bring closure to families, and find answers that once seemed lost to time.