UCLA. US: A new UCLA study is
the first to demonstrate that Down syndrome accelerates aging in
different parts of the body.
The researchers showed that the biological
age of brain tissue from someone with Down syndrome appeared 11 years
older than the person’s chronological age. Similarly, the biological age
of blood tissue was nearly five years older than the person’s
chronological age. The UCLA team will next test tissue samples from
teens with Down syndrome to pinpoint when aging speeds up in people with
the condition.
IMPACT
The findings could explain why people with Down syndrome face a six
times higher risk of developing Alzheimer’s disease and their average
life expectancy is only 60. Alzheimer’s strikes 75 percent of
individuals with Down syndrome who live past 65.
METHOD
The scientists used an epigenetic clock, which tracks chemical
reactions that trigger and turn off areas of the genome, to measure the
age of different tissues in the body. The team focused on methylation, a
molecular biomarker linked to aging.
BACKGROUND
Down syndrome is a genetic disorder caused by an extra copy of
chromosome 21. Its symptoms include cognitive delays and premature signs
of aging, including wrinkled skin, gray hair, early menopause,
declining immune function and Alzheimer’s disease. According to the
National Down Syndrome Society, about 400,000 Americans have Down
syndrome and some 6,000 babies are born with the condition in the United
States each year.
AUTHOR
Steve Horvath, a professor of human genetics and biostatistics at the
David Geffen School of Medicine at UCLA and
UCLA Fielding School of Public Health, is available for interviews.
FUNDING
The research was supported by a grant from the National Institute of Aging.
JOURNAL
The peer-reviewed journal Aging Cell published the
findings in its Feb. 9 online edition.