Breakthrough: The Trauma Tracer

This video is a part of Breakthrough, a short film anthology from Science Friday and Howard Hughes Medical Institute (HHMI) that follows women working at the forefront of their fields..

a blue paint circle badge with words in white that say "best of 2020"Growing up, “family” meant something very different to Bianca Jones Marlin. Her biological parents provided foster care to multiple children, giving Marlin the joy of having many siblings from an array of different backgrounds. On occasions, she would stay up late listening to the stories from her siblings’ past homes—stories filled with trauma and sadness. These stories had a profound and lasting impact on Marlin.

“There were stories of abuse, of not getting the proper nutrition or proper care that a child would need,” Marlin says. “Taking my passion for science and what I’ve learned from them, and putting them together is really my angle.”

Today as a neurobiologist, Marlin researches how trauma can be passed down from generation to generation. At Columbia University’s Zuckerman Institute, she studies the molecular mechanisms of stresses in parents that can affect the brain structure and sensory experiences of their future offspring.

Marlin’s investigations examine a process known as epigenetic inheritance, in which biochemical markers acquired from experiences or environmental conditions can alter how our genes are expressed inside of cells. In the case of the mice she works with, Marlin creates a stressful association with a particular odor, which in turn increases the number of olfactory cells inside the mices’ brains used to detect that specific smell. She then looks at whether or not the offspring are born with more of these olfactory cells as a result of their parent’s trauma. If that proves to be true, Marlin plans to find and potentially even modify the epigenetic switches responsible for changing the children’s biology or behavior—ultimately improving the outcomes for the children.

“This is a proxy to the human experience because during a traumatic event, we are still using our senses to create those memories,” says Marlin. “What we’re exploring is if these memories are actually then passed down to the subsequent generations and what that would look like biologically.”


Further Reading

  • Learn more about Bianca Jones Marlin’s research on her website.
  • Watch a video lecture by Marlin at the American Museum of Natural History.

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Directed and Produced by Chelsea Fiske

Director of Photography Luke Groskin, Brandon Swanson, Devin Powell

Edited by Erika Sutter and Luke Groskin

Animations by Lottie Kingslake

Music by Audio Network

Series Producer Luke Groskin

Additional Photos And Videos by Bianca Jones Marlin, Pond5, Shutterstock, OX Creative/Film Supply, Evolve Studios Beedlbank WW2 NIOD Institute for War, Holocaust and Genocide Studies

Project Advisors for HHMI Tangled Bank Studios Richard Stone and Aileen O’Hearn

Project Support for Science Friday Initiative Danielle Dana, Jennifer Fenwick, Ariel Zych Nadja Oertelt, Kyle Marian Viterbo, Diana Montano Daniel Peterschmidt, Xochitl Garcia, Nahima Ahmed

Special Thanks Bianca Jones Marlin, The Jones Family, The Zukerman Institute

Meet the Producers and Host

About Chelsea Fiske

Chelsea Fiske is a video producer with Moonjelly Productions in Seattle, Washington.

About Luke Groskin

Luke Groskin is Science Friday’s video producer. He’s on a mission to make you love spiders and other odd creatures.

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