The Doctor Who Put Children on the Cell Map
Deanne Taylor saw a $38.5M gap in biomedical research. Now she's building the first gene-expression baseline for kids.
By The Science Desk
A researcher was unveiling the Human Cell Atlas—an effort to map every cell in the human body—and the plan covered only adults [1].
The field's dominant view, she says, was that children are exactly like small adults [1]. They are not. Children's cells differ from adults' in how they express genes—switching them on and off or turning them up or down—and those variations can cause drastically different and even deadly responses to drugs that adults tolerate well [1]. Because of the way cardiac genes are expressed in children, for instance, chemotherapy drugs can attack not only tumors but also children's developing hearts, potentially causing lifelong damage [1].
Taylor moved fast. That paper argued for a Pediatric Cell Atlas as part of the Human Cell Atlas consortium—providing single-cell profiles and spatial characterization of gene expression across human tissues and organs [2]. "It put a flag in the ground," Taylor says. "Why don't we have healthy models of children's development?" [1]
The push produced results. In 2021 the NIH awarded a $38.5 million grant to the Developmental Genotype-Tissue Expression Project, or dGTEx—a major initiative aimed at establishing the first comprehensive database of healthy pediatric tissue [1]. The project banks samples collected from otherwise healthy children who have died and whose parents agreed to donate their bodies, then maps how genes across all the major organ systems are expressed [1]. Taylor and her team curate and standardize each donation's associated data, from family history to sample details; a separate group analyzes the samples themselves; and the information is combined into a single baseline [1].
What makes this work consequential is not just the database itself, but what it reveals about the assumptions medicine has long taken for granted. Treating smaller bodies as scaled-down versions of larger ones was never biology—it was convenience.
The stakes are clearer when you consider what the Human Genome Project left unfinished. That effort, which wrapped up in 2003, helped researchers link specific genes to specific diseases [1]. But a map of the genome, Taylor notes, is a bit like a DIY kit with all the parts and no assembly manual—it doesn't tell you where and how cells use each gene throughout the body [1]. The dGTEx database aims to fill that gap for children: a molecular map of how the body's roughly 20,000 genes do their work in healthy tissue cells [1]. Single-cell gene expression analyses have already uncovered profound stage-specific molecular regulatory phenomena that have changed the understanding of unique cell types and signaling pathways critical for lineage determination, morphogenesis, and growth [2].
Taylor's role extends well beyond data curation. She is a principal investigator for the Kids First Data Resource Center, which sequences diseased tissues collected from children enrolled in studies nationwide, and she has been collaborating with researchers on HubMAP, an effort that's building a resource complementary to the Human Cell Atlas, to secure funding to create 3D maps of children's cells [1]. Sarah Teichmann, a cofounder of the Human Cell Atlas, describes Taylor's contribution in broad terms: "Deanne took a big-picture view and said, We don't just need to understand the pediatric kidney or the pediatric brain or the pediatric immune system. We need a holistic view of pediatric development" [1]. Rebecca Linn, a pediatric pathologist at CHOP, puts the logistics more bluntly—coordinating researchers across this many organizations is "like herding cats" [1].
The science behind the urgency is developmental: much of human biology is set during childhood. Key brain cells called astrocytes form in the first five years; the immune system matures in puberty [1]. Extending the atlas to children may even reveal how adult diseases trace back to distinct signals in childhood—raising the possibility of screening for and treating chronic conditions years or decades before they surface [1]. Such data could also provide a rich cytogenomic framework for understanding environmental and genetic impacts across the human lifespan [2].
The deeper implication is that pediatric biology isn't a subcategory of medicine to be addressed after adults are mapped. It is, in many ways, where the map should have started.
Taylor describes her own career as a "random walk," driven by a singular intensity she now attributes to undiagnosed autism and ADHD; despite this seemingly winding road, she says her focus has always been on understanding why the same illness hits people differently [1]. The atlas she is helping build may finally give researchers the tools to answer that question—not just for children, but for everyone who was once one. "By ignoring the pediatric side of things," she says, "I think people are missing a window of intervention in human disease" [1].
By ignoring the pediatric side of things, I think people are missing a window of intervention in human disease.Deanne Taylor