An Obesity Gene, Known as FTO, Also May Increase Risk of Alzheimer's Disease and Dementia
- When Combined with a Known Alzheimer's Gene, Your Alzheimer's Risk may be Doubled -
HONOLULU, July 12 /PRNewswire-USNewswire/ -- A gene known as
FTO, which appears to be correlated with obesity in humans, may
also increase risk of Alzheimer's disease and dementia, according
to new research presented today at the Alzheimer's Association
International Conference on Alzheimer's Disease 2010 (AAICAD 2010)
in Honolulu, HI. And when a person has certain variants of both FTO
and a recognized Alzheimer's risk gene known as APOE, the risk of
Alzheimer's could be doubled.
"While scientists know Alzheimer's involves progressive brain
cell failure, they have not yet identified any single reason why
cells fail," said Maria Carrillo, PhD, senior director of Medical
and Scientific Relations at the Alzheimer's Association. "However,
there is evidence about certain factors that may increase the
likelihood of developing Alzheimer's."
"Some of these factors we can't control, such as age, family
history, and genetics," Carrillo said. "Others we may be able to
influence, including heart health, tobacco and alcohol use, and
head injury."
FTO has previously been shown to affect body mass index (BMI),
leptin levels (a protein hormone that plays a key role in appetite
and metabolism), and the risk for diabetes. These vascular risk
factors have also been associated with risk of Alzheimer's
disease.
In the study reported at AAICAD 2010, Caroline Graff, MD, PhD,
and colleagues at the Karolinska Institutet, Sweden, explored the
direct role of the FTO gene on Alzheimer's and dementia risk in old
age. In addition, a possible interaction of FTO with the APOE gene,
a well-established genetic risk factor for Alzheimer's, was
assessed. The researchers followed 1,003 people aged 75 years and
older without dementia from the Kungsholmen project, Sweden, for
nine years to detect new cases of Alzheimer's and dementia. All
participants had been genotyped for FTO and APOE on DNA sampled at
the beginning of the study.
They found that people in the study population who carried the
AA gene-variant in the FTO gene had a 58 percent increased risk for
developing Alzheimer's and a 48 percent increased risk for
developing dementia compared with those who did not have this
genetic variant, after adjustment for age, gender, education, and
APOE genotype.
The findings also suggest that the risk-effect of FTO-AA on
dementia is further elevated to 100 percent increased risk in the
presence of APOE epsilon4, which is the highest risk variant of the
APOE gene. The effect of the FTO-AA genotype on Alzheimer's and
dementia risk remained after additional adjustment for diabetes,
BMI, cardiovascular disease and physical inactivity.
"One of the intriguing aspects of the results is that the
increased risk was independent of the traits previously associated
with FTO, such as obesity and diabetes measured at baseline," Graff
said. "Our results suggest that the mechanism by which FTO is
associated with an increased risk for Alzheimer's and dementia may
be different from how it increases the risk for obesity."
"This is a fascinating early finding, which fits with the known
connections between heart health and brain health," Carrillo said.
"However we do need to see these results confirmed by other
researchers. In fact, we desperately need to know more, in general,
about the genetics and other causes of Alzheimer's so that we have
additional targets for therapies and preventions. One major
positive step in that direction would be for the federal government
to address its chronic underfunding of Alzheimer's disease
research."
About AAICAD
The Alzheimer's Association International Conference on
Alzheimer's Disease (AAICAD) is the world's largest conference of
it's kind, bringing together researchers from around the world to
report and discuss groundbreaking research and information on the
cause, diagnosis, treatment and prevention of Alzheimer's disease
and related disorders. As a part of the Alzheimer's Association's
research program, AAICAD serves as a catalyst for generating new
knowledge about dementia and fostering a vital, collegial research
community.
About the Alzheimer's Association
The Alzheimer's Association is the leading voluntary health
organization in Alzheimer care, support and research. Our mission
is to eliminate Alzheimer's disease through the advancement of
research, to provide and enhance care and support for all affected,
and to reduce the risk of dementia through the promotion of brain
health. Our vision is a world without Alzheimer's. Visit
www.alz.org or call 800-272-3900.
-- Caroline Graff, et al. The obesity related gene, FTO, increases the
risk for incident Alzheimer disease in a prospective population based
study. (Funded by: Swedish Brain Power Initiative, Karolinska
Institutet's Faculty funding for postgraduate students, Swedish
Research Council in Medicine, Forskningsradet for Arbetsliv och
Socialvetenskap (Sweden), Anslag forskning och utveckling (FAS,
Stockholms lans landsting), the Gun & Bertil Stohne's Foundation,
Marianne and Marcus Wallenberg Foundation, Swedish Alzheimer
Foundation, Gamla tjanarinnor Foundation.)
Source: Alzheimer's Association
CONTACT: Alzheimer's Association media line:
+1-312-335-4078,
media@alz.org, AAICAD 2010 press room,
July 10-15: +1-808-792-6523
Web Site: http://www.alz.org/
Posted: July 2010
