Home' Australian Pharmacist : Australian Pharmacist April 2013 Contents 20 Australian Pharmacist April 2013 I ©Pharmaceutical Society of Australia Ltd.
Ancient DNA reveals e ects of changing diets
Tartar from ancient teeth is helping
researchers map the effect of dietary
changes on human health.
DNA from tartar preserved on the teeth
of ancient skeletons has revealed the
consequences of changes in human diet
and health from the Stone Age to modern
day. The ancient genetic record reveals
the negative impact and changes farming
and manufactured foods have had on the
evolution of our oral bacteria.
An international team, led by the University
of Adelaide's Centre for Ancient DNA (ACAD),
along with the University of Aberdeen and
the Sanger Institute at Cambridge, published
the results in the 17 February issue of
Professor Keith Dobney,
Sixth Century Chair of
at the University of
Aberdeen, said: 'This
provides us with
a completely new
window on how people lived and died in
the past. Knowing the real genetic history of
diseases we still suffer from today will help us
better understand and even treat them.
'Being able to track them through time
has huge implications for understanding
the origins and history of human health --
making the archaeological record extremely
relevant and important to modern-day
medics and geneticists.'
The researchers extracted DNA from tartar
(calcified dental plaque) from 34 prehistoric
northern European human skeletons,
and traced changes in the nature of oral
bacteria from the last hunter-gatherers,
through the first farmers to later Bronze Age
and Medieval times.
Study leader and Director of ACAD Professor
Alan Cooper said: 'This is the first record of
how our evolution over the last 7,500 years
has impacted the bacteria we carry with us
and their important health consequences.
'Oral bacteria in modern man are markedly
less diverse than historic populations and
this is thought to contribute to chronic oral
and other disease in post-industrial lifestyles.'
The development of farming around 10,000
years ago caused a major shift in human
diet, resulting in a significant impact on
our health. The same was true of the more
recent move to eating highly processed
flour and sugar, both of which have
contributed directly to health problems we
see today such as tooth decay, diabetes and
Professor Cooper said: 'The composition
of oral bacteria changed markedly with
the introduction of farming, and again
around 150 years ago. With the introduction
of processed sugar and flour during
the Industrial Revolution, we can see a
dramatically decreased diversity in our
oral bacteria, allowing domination by
caries-causing strains. The modern mouth
basically exists in a permanent disease state.'
Ironically, the introduction of sugar and
carbohydrates contributed to the increase
in dental plaque that now holds the vital
information the scientists are studying.
Professor Dobney said: 'Until now we've
had to rely mainly on indirect evidence or
historical documents to tell us what people ate
and what kind of illnesses they suffered from
in the past. But now we can directly extract
genetic information on diet and health from
the tartar on teeth -- which is very abundant
and well-preserved in the archaeological
record - we have a totally new source of
unique information stretching back thousands
Dr Julian Parkhill, co-author from the Wellcome
Trust Sanger Institute, said: 'We have shown
that genetic sequencing is not restricted
to modern samples. Sequencing the oral
microbiota of different populations, over the
ages, from across the world will tell us how
different diets have affected human health,
opening a whole new area of research.'
Professor Dobney and Professor Cooper
have been working on the project for
the past 17 years but only since 2007
has it been possible to carry out the
research as a result of ACAD's ultra-clean
laboratories and strict decontamination and
Previous studies of early skeletons have shown
a range of pathologies associated with the
introduction of farming during the Neolithic
(farming age), including a marked reduction in
average population height, nutritional stress
during youth, and increases in diseases such
as arthritis and tuberculosis. These are thought
to relate to the change from the diverse
hunter-gatherer diet to one based mainly
on carbohydrates from crops such as wheat,
barley and rye.
The studies of dental calculus on the last
hunter-gatherers, and early farming skeletons
reveal a major change in oral microbes, with an
overall reduction of diversity and an increase
in bacteria associated with gum disease
(periodontitis) and dental caries (holes in
The research team is now expanding studies
through time, and around the world, including
other species such as Neanderthals.
Late Iron Age/Roman woman showing large dental calculus deposit, from Cambridge area, UK.
A man from Europe's first farming culture, around 7,000 years
ago, showing dental calculus and growth lines on one tooth
characteristic of nutritional stress during youth.
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