Published online: 12 April 2007; | doi:10.1038/news070409-10 /
http://www.nature.com/news/2007/070409/full/070409-10.html
First monkey genome sequenced
New genome has scientists going bananas.Erika Check
| The rhesus macaque : 93% like you and me. Getty |
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In
some ways, macaque monkeys are a lot like people: they can reside in
cities, eat everything from peanuts to ice cream, and prefer to live in
communities. Research published today will help scientists to figure
out any genetic reasons behind these similarities - and behind our
differences, from the macaques' short size and hairy bodies to their
vulnerability to disease.
Writing in the journal
Science
today, researchers present the DNA sequence of the rhesus macaque, a
species of monkey living all across Asia. Old-world monkeys such as the
macaque are thought to have diverged from the primate line that led to
humans some 25 million years ago. But an in-depth study of portions in the new sequence reveals that we are still 93% identical in our DNA.
Knowing
the sequence of the macaque genome is important to scientists because
captive-bred macaques are often used in tests of experimental drugs and
medical treatments. Understanding how they differ from us should help
to better predict when a drug will have a different effect on humans
than it did in animal tests. But the macaque sequence is also exciting
for scientists because it should help them learn more about what makes
us human.
Compare and contrast"When
you sequence the genome of a non-human primate, you open the door to
understanding the biology of an animal that's really closely related to
us, and that's very exciting," says George Weinstock of the Baylor
College of Medicine in Houston, Texas, a leader of the macaque
sequencing effort.
Scientists
sequenced the chimpanzee, a much more recent relative and closer cousin
of ours, in 2005, showing that we are 98% identical in DNA. The macaque
genome provides a third reference point in comparing these two. So, for
instance, if scientists find a DNA difference between humans and
chimps, they can check it against the macaque sequence to figure out
whether the chimp or the human carries the more ancient version of the
DNA.
By
performing such comparisons, scientists hope to be able to home in on
regions of the genome that contributed to the evolution of humans. This
method will become even more powerful over the next few years, as
scientists add other non-human primate genomes to the mix: the gibbon,
the marmoset, the orangutan and the gorilla are all on the cards.
Sweet toothThe macaque genome has already provided some insight into evolution.
One
gene group that has massively expanded in the macaque, as compared with
the human, is important to sugar digestion. Perhaps this is a genetic
adaptation that allowed macaques to start eating a fruit-heavy diet,
the researchers speculate.
The scientists' analysis also points out that many of the
types of genes that differ between macaques and humans are found in our
immune systems, which orchestrate our bodies' defences against disease.
By studying these differences, scientists might be able to fine-tune
their use of the macaque as a stand-in for people in medical
experiments.
"Having a macaque genome means they can be used more wisely in research," Weinstock says.
References- Rhesus Macaque Genome Sequencing and Analysis Consortium. Science,
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