There's no substitute for clinical acumen in medicine. Without it, UC Davis M.I.N.D. Institute
Medical Director Randi Hagerman would not have discovered a previously unrecognized disease. An internationally
renowned expert on fragile X syndrome an in heritable form of mental retardation in children
Hagerman noticed something unusual in the concerns mothers of her young patients expressed about the health
of their own fathers.
"Some of their fathers the grandfathers of the children with fragile X syndrome were shaking so
much that they couldn't drink a glass of water without spilling it," said Hagerman. "Many fell for no
apparent reason and were developing dementia."
Clinical skill was, of course, the key to noticing these puzzling findings, yet a number of imaging technologies
are helping to unlock their mysteries. Randi and her husband, Paul Hagerman, a UC Davis School of Medicine
professor, molecular biologist and physician, began to tackle the problem using every tool available.
The grandfathers were carriers of a "premutation" form of the fragile X mental retardation
1 (FMR1) gene on the x-chromosome, the same gene that has undergone a full mutation in children with fragile
X syndrome. The Hagermans named this previously unidentified disease fragile X-associated tremor/ataxia
syndrome, or FXTAS ("FAX-tass").
Claudia Greco, UC Davis assistant professor of pathology, analyzed brain samples from patients with FXTAS
who died. She found curious spherical inclusions in the nuclei of neurons and astrocytes throughout the
cortex and brain stem.
Immunofluorescence imaging in Paul's laboratory, coupled with state-of-the-art fluorescence cell sorting
technology, enabled the researchers to purify these inclusions. The Hagermans, in collaboration with Carlito
Lebrilla, professor of chemistry at UC Davis, are using advanced mass spectrometric methods to identify
the proteins within the inclusions.
James Brunberg, Chair of the Department of Radiology at UC Davis Medical Center, examined MRI brain scans
of the affected men and discovered unusual features common to many: symmetric bright spots in the middle
cerebellar peduncles and adjacent cerebellar white matter. These unique features are now part of the criteria
for diagnosing the disease.
The Hagermans hope their research will help stave off FXTAS in men who are genetically prone to it. "The
great thing about being at an institution like UC Davis is the opportunity for collaboration," said Paul.
"We have so many specialists available to us in so many different fields."