Brain Folding and Canids: A look at the TRNP1 Gene

The intricate folding of the mammalian brain, known as cortical folding or gyrification, is a marvel of evolution, allowing a large surface area to fit within the confines of the skull. A recent study led by researchers

Dr. James Sacco, a pharmacologist at Drake University, and Dr. Muhammad Spocter, an evolutionary neuroanatomist at Des Moines University, sheds light on how genetic variations in the TRNP1 gene influence brain folding in domestic dogs and their wild relatives. This groundbreaking research not only deepens our understanding of canine brain evolution but also highlights broader implications for brain development across species.

The study focuses on the TRNP1 gene, which plays a critical role in regulating cortical expansion and folding. By sequencing this gene in 72 canids—including dogs, wolves, coyotes, and foxes—the researchers identified 30 genetic variations. Interestingly, dogs exhibited the least genetic diversity, a likely result of domestication and selective breeding. Some of these variations may alter TRNP1 function by affecting how other molecules bind to its regulatory regions. These changes could influence the development of neural progenitor cells, ultimately shaping brain structure.

Dr. Spocter explains: “This work provides compelling evidence that differences in TRNP1 could underlie the unique patterns of brain folding seen in carnivores. Understanding these genetic mechanisms is crucial for unraveling how brain structure influences behavior and cognition.”

The study uncovered two significant coding sequence changes—one exclusive to dogs and another found only in canids compared to other mammals. These changes may affect the protein's structure and function.

In addition, the team also uncovered some evidence for the effects of domestication. In particular they found that the reduced genetic diversity in dogs aligns with their domestication history, which has also shaped their skull morphology and brain architecture.Variations in TRNP1 were also observed across different canid species, providing a comparative framework for studying brain evolution.

This research is part of a growing effort to understand how genes like TRNP1 contribute to brain complexity across species. 

For students inspired by this work, Des Moines University's Master of Science in Anatomy (M.S.A.) program offers an excellent opportunity to explore comparative neuroanatomy and evolutionary biology. Explore Des Moines University's Master of Science in Anatomy program for advanced training in anatomy and neuroanatomy. Visit Drake University and Des Moines University to learn more about their contributions to cutting-edge research.

For those interested in diving deeper into the study, you can access the full article here: Resequencing of the TMF-1 (TATA Element Modulatory Factor) regulated protein (TRNP1) gene in domestic and wild canids.This collaborative research highlights how interdisciplinary approaches can unlock new insights into the mysteries of brain evolution—one fold at a time!