ALS, Dementia Linked to Chromosome 9

Neurologist Robert Brown, who heads the MDA/ALS Center at Massachusetts General Hospital in Boston, was part of a team that studied a 50-member Scandinavian family in which five people carried a diagnosis of amyotrophic lateral sclerosis (ALS) and nine a diagnosis of frontotemporal dementia (FTD), a disorder characterized by behavioral disturbance and personality change.

Although there were no family members who had ALS and FTD, the researchers, who published their findings online Jan. 18 in Neurology, say they think a single cause, arising from a gene on chromosome 9, probably underlies both conditions, with additional factors determining whether the result is ALS or FTD.

Brown says he thinks there may already be 20 to 30 families in which the chromosome 9 gene variant is the cause of ALS.