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Researchers Find Cause For Type Of Dementia

Michael Hutton (seated) and his team of researchers hope the gene mutations they've identified as triggers of a common form of dementia will one day provide the means to cure Alzheimer's, Parkinson's and possibly Lou Gehrig's diseases.

Mayo Clinic neurobiologist Michael Hutton, Ph.D., led a team of researchers who discovered that mutations in the progranulin gene cause frontotemporal dementia (FTD), the second most common form of dementia. Researchers identified nine mutations that effectively knock out a copy of the gene. Those with one of the mutations almost invariably get the disease if they live long enough.

It's actually a group of brain disorders that affect the frontal and temporal lobes of the brain, which control personality and speech. Patients usually retain memory until later in the disease course. This differentiates FTD from Alzheimer's disease, where memory function is affected early on.

In 1996 researchers first linked a genetic cause for FTD to chromosome 17. In 1998 Hutton and others discovered mutations in a gene on chromosome 17 that codes for a protein called tau. However, many FTD-affected families with genetic linkage to chromosome 17 lacked these mutations, so researchers continued to hunt for an additional culprit gene or genes.