Fragile X's Unwelcome Relative

Fragile X is the most common from of mental retardation. Dr. Randi Hagerman, after many years of treating patients with Fragile X, discovered that there was one awfully common detail to many of her patients situations.

Before, it was almost impossible to predict the possibility of a mother to pass on a mutation of the X chromosome on to her offspring, but after hearing many similar stories of mother's of the patients with Fragile X, Dr. Hagerman decided that it could not be a coincidence. "I'm concerned about my father, he's falling down a lot," was what Dr. Hagerman heard too often from these patients' mothers and decided to start a research.

With research, Dr. Hagerman discovered that maternal grandfathers, primarily, have a newly identified disorder, Fragile X-associated tremor ataxia syndrome (FXTAS). Studies by Dr. Hagerman and others, have linked FXTAS to the same gene responsible Fragile X. "Some of the men have daughters who may be thinking about starting families, Hagerman notes, and the pattern of inheritance means that all these women carry the premutation: 'They didn't know they were carriers, and that's very important information for them.'"

Photo description and credits:

Signs of trouble.

An MRI scan (top) reveals degeneration characteristic of FXTAS. In postmortem tissue (bottom), protein inclusions in neurons (dark arrow) and astrocytes (open arrow) are hallmarks of the disease.

CREDITS (TOP TO BOTTOM): P. J. HAGERMAN; COURTESY OF C. GRECO/UC DAVIS

Read the complete article: http://www.sciencemag.org/content/312/5773/518.full