Decoding a Killer

collage of newspaper images, charts and photographs

When Barbara Rae-Venter ’72, PhD ’76, retired from her career in patent law in 2005, she was looking forward to a different kind of work—working on her tennis game for one thing, or exploring her family history, maybe finding that long-lost cousin she’d heard about. She certainly did not expect to be collaborating with law enforcement to catch some of the nation’s most notorious killers. But when the call came, she answered, and has since helped solve more than 40 cold cases. Retirement, it would seem, can wait.

Today, Rae-Venter is recognized as a trailblazer in the nascent field of investigative genetic genealogy. But her story began decades earlier at UC San Diego, where—as a biology student in the ’70s—she was exposed to the burgeoning field of DNA science. Ultimately, she would couple this knowledge with new genealogy and ancestry-mapping skills and create a novel method of identifying and narrowing down criminal suspects. It’s a development only made possible by the recent surge in consumer DNA testing and the availability of huge genetic databases, enabling people—including sleuthing genealogists—to connect the genetic dots in a way never before possible.

No one could have anticipated such a confluence of events, including Rae-Venter. Her genealogical journey began with explorations of her own family tree, but she soon became proficient enough to volunteer as a “Search Angel” with DNAAdoption, an organization that teaches adoptees how to identify their birth relatives using autosomal DNA, the genes that govern trait inheritance.

Her work as a “Search Angel” eventually included a project for the Crimes Against Children Detail of the San Bernardino County Sheriff to identify the immediate family of Lisa Jensen, a woman in her 30s who was abducted as an infant. In 2016, after many hours of searching publicly available genetic databases and building two very large family trees, Rae-Venter successfully identified Jensen’s biological mother, which subsequently revealed that Jensen’s abductor—her mother’s live-in boyfriend at the time—had committed a string of murders in California and New Hampshire.

“Lisa’s abductor—a man of many aliases who abandoned her when she was five years old—had been convicted of murdering his common-law wife in Contra Costa, Calif.,” explains Rae-Venter. “By utilizing crime scene evidence and DNA profiles uploaded by family members, we were ultimately able to determine the true identity of this man, Terry Peder Rassmussen. We also confirmed that he was a serial killer.”

Man in orange jumpsuit in a courtroom, seated in a wheelchair
Former police officer Joseph DeAngelo evaded law enforcement for more than three decades, until Venters techniques led to his recent arrest and conviction.

In March 2017, news of Rae-Venter’s success in the case reached Paul Holes, chief of forensics in the Contra Costa County D.A.’s office, who had been trying to crack the notorious “Golden State Killer” case for more than two decades. While police had long-suspected that a series of rapes and killings up and down California in the ’70s and ’80s could have been the work of one man, it wasn’t until 2001 that DNA testing confirmed the theory. The man’s identity, however, remained a mystery.

Rae-Venter agreed to help on the case and uploaded a crime scene DNA sample in GEDmatch, a genetic family tree database. Rae-Venter then guided Holes’ team in constructing family trees to discover relatives corresponding to the DNA, a painstaking and laborious process that involves tracing lineage back to a common ancestor—great-great-great-grandparents, in this case—then looking forward and building out the many branches of multiple family trees. With additional pieces of evidence, such as ethnicity and key physical features helping to winnow down leads, Rae-Venter was able to confidently identify a likely suspect. Law enforcement obtained a DNA sample, which matched the crime scene DNA and confirmed that former police officer Joseph DeAngelo was the Golden State Killer. Arrested in August 2018, DeAngelo pled guilty to all crimes—at least 13 murders, 50 rapes and 120 burglaries—and was sentenced to life in prison.

“It was an extraordinary experience,” says Rae-Venter. “Besides the incredible teamwork required, there were two key factors in the positive I.D.—a DNA profile of a cousin of DeAngelo’s uploaded to the database, and my ability to determine that the likely suspect was blue-eyed and, by this time, bald. When I was able to narrow the pool of suspects to identify DeAngelo, it felt very gratifying to play such a key role in getting this man who had committed such horrific crimes off the street.”

Rae-Venter’s work on the case made her one of Nature magazine’s “Ten People Who Mattered in Science in 2018,” as well as one of Time’s “100 Most Influential People of 2019.” In the Time listing, Paul Holes wrote, “Since DeAngelo’s arrest in April 2018, more than 25 horrific cold cases—many of which had frustrated their investigators for decades—have been moved forward. Rae-Venter has provided law enforcement with its most revolutionary tool since the advent of forensic DNA testing in the 1980s.” In her post-retirement second career, Rae-Venter has guided multiple law enforcement teams on how to best structure their own investigative genetic genealogy teams for maximum efficacy and accuracy.

Her tennis game hasn’t progressed, but Rae-Venter doesn’t seem to mind; she finds her newfound genetic sleuthing both rewarding and addictive, and is pleased to have launched such an impactful post-career niche. It’s a path that has led her full circle, drawing upon her early interest in the science behind genetics and her subsequent training as a scientist at UC San Diego.

Starting as a Muir student in the late ’60s, Rae-Venter pursued a double major in biology (specifically biochemistry, then a special projects major) and psychology. Overall, however, Rae-Venter credits her UC San Diego professors for helping to create an inclusive, engaging and supportive environment that was conducive to learning and collaboration.

“The faculty were really phenomenal,” she recalls. “The fluidity within the campus and the collaboration across labs—not just at UCSD but across the mesa—was really a boon for a student in the biological sciences like me.”

Man in a physicians white coat with woman with brown hair in black graduation gown
Venter at graduation with her thesis advisor, biochemist Nathan Kaplan, an early influence in her lifelong scientific interests.

Rae-Venter remembers her thesis adviser—Nathan Kaplan, who chaired the graduate-level biochemistry department—with a special fondness. Kaplan was also the thesis advisor for J. Craig Venter, her fellow student and husband during her six years at UC San Diego, who also went on to make a huge splash in the field of human genetics.

“Back in those early days, we all sat in desks lined up along the main corridor of the fourth floor of the Basic Science building, and Professor Kaplan would stroll up to us and would engage us in a stimulating, freewheeling brainstorming session. This would happen at least a few times a week,” she says, “and it was marvelous.”

Rae-Venter also recalls a pre-med genetics class with Dan Lindsley, which fueled her interest in genetics. Lindsley, the pioneering drosophila geneticist known by students as ‘Dr. Fruit Fly,’ developed the first comprehensive organismal genetic/genomic database. He was also a strong advocate for lab experimentation and had a hands-on approach to science and teaching.

Armed with these rich experiences and a doctorate in hand, Rae-Venter worked as a postdoc fellow and a cancer researcher before accepting a faculty position at the University of Texas Medical Branch in Galveston, Texas. A few years later, while serving on an admissions committee, she found that the questions she was most interested in asking students revealed a strong interest in the legalities of medical ethics. She decided to take the LSAT, and soon enough, she was a UT Austin law student, as well as a clerk at a local law firm, where she became fascinated with medical ethics issues, such as euthanasia and where frozen embryos go when the parents die or divorce.

By the time she earned her law degree in the mid-1980s, biotech was about to boom. With her science background and drive to be at the cutting-edge of scientific developments, Rae-Venter found herself back in California, well-poised to join the patent law practice of biotech pioneer Bertram Rowland, who introduced the transformative Cohen and Boyer cloning patents. With Rowland, Rae-Venter supported the start-up of several biotech firms and prosecuted more than 150 patents. During her 20-year career, she worked on hundreds of biotech patents that made waves in the industry, including the “Flavr Savr” Tomato, considered to be the first genetically modified fruit.

“For someone interested in the science behind inventions, it was an amazing field to be in,” says Rae-Venter. “Since everything was new to some extent, it was a process of constant learning. Very exhausting but also very stimulating.”

It seems constant learning is a pattern in Rae-Venter’s life. And while her post-career vocation of genetic genealogy has been equally exhausting and stimulating, she has no intention of relaxing at this point. In fact, she is currently working with law enforcement on another 50 criminal cases that have gone cold.

“I hope my career is a testament to that fact that a solid grounding in the biological sciences can propel you in any number of directions,” says Rae-Venter. “Look how many times I’ve ‘reinvented’ myself—from cancer researcher to biotech patent attorney to genetic sleuth. Even after a long career, I’m still reinventing.”


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