UAMS Neurologists Discover New Neurodegenerative Disease
Jan. 10, 2013 | Two University of Arkansas for Medical Sciences (UAMS) neurologists are part of a multi-institutional team that has identified a new neurodegenerative disease that is associated with increased deposits of iron in the brain.
Brain MRI scans revealed iron buildup in distinct areas of the brain, especially in the basal ganglia (subtantia nigra and globus pallidum), leading scientists to the discovery.
The discovery was published last month in the American Journal of Human Genetics. The entire paper, “Exome Sequencing Reveals De Novo WDR45 Mutations Causing a Phenotypically Distinct, X-Linked Dominant Form of NBIA,” can be found here.
The new disease is called BPAN (beta-propeller protein associated neurodegeneration) and was discovered in 20 patients whose symptoms included early-onset developmental delay and other neurological deterioration associated with Parkinson’s disease, dystonia and dementia by early adulthood. Brain MRI scans revealed iron buildup in distinct areas of the brain, especially in the basal ganglia (subtantia nigra and globus pallidum), leading scientists to the discovery.
“There are very few diseases that show iron accumulation like what we saw in MRI,” said Sami I. Harik, M.D., professor in the UAMS Department of Neurology. “Through an exome sequencing process, the entire patient’s genome was examined and the new disease was pinpointed.”
Along with Harik, Vasuki H. Dandu, M.D., who until recently was a senior neurology resident at UAMS, assisted a team of researchers from nearly a dozen institutions in the United States, Europe and Canada who contributed to the discovery.
Neurodegeneration with brain iron accumulation, known as NBIA, is a group of single-gene disorders that manifest a range of neurologic expressions, all having iron buildup in common. To date, only a small group of genes associated with NBIA have been identified. As those disorders were ruled out in the study patients, the researchers suspected that a never-before identified gene was responsible. The researchers found mutations in the “WDR45” gene, located on the X chromosome,that was the cause of this unique form of NBIA.
The WDR45 gene that was mutated encodes for a beta-propeller protein-associated neurodegeneration, or “BPAN.” The beta-propeller protein acts as a “chaperone,” Harik said, that plays an integral role in packaging and exporting waste products out of the cell.
“Discoveries like these are really pushing the frontiers of science,” Harik said. “It shows that we are not only delivering quality health care to Arkansans, but we’re also doing work that is on the leading edge of discovery and moving science forward.”