IRP scientists discover a rare neurological disease involving cellular recycling

Friday, February 10, 2023

New disease could provide insights into how the cell’s recycling system contributes to a healthy brain

Researchers at the National Institutes of Health have discovered a new neurological condition characterized by issues with motor coordination and speech. They report their findings in npj Genomic Medicine.

Scientists from NIH’s National Human Genome Research Institute (NHGRI) and Undiagnosed Diseases Program (UDP) identified three children with the condition, two siblings and an unrelated child. The three children all had issues with motor coordination and speech, and one child had abnormalities in the cerebellum, the part of the brain involved in complex movement among other functions. Additionally, the children all had mutations in both copies of the ATG4D gene.

ATG4D aids in the cellular housekeeping process called autophagy, which cells use to break down and recycle damaged proteins and other defective pieces of the cell to stay healthy. Autophagy is a fundamental process used by cells throughout the body, but neurons are particularly dependent on autophagy for survival. However, little is known about how ATG4D contributes to healthy neurons.

“Among genetic diseases, we’ve solved many of the lower hanging fruits,” said May Christine Malicdan, M.D., Ph.D., NHGRI staff scientist and senior author of the study. “Now, we’re reaching for the higher fruits — genes like ATG4D that are more difficult to analyze — and we have the genomic and cellular tools to do so.”