ScienceCache
Vol. 169
April 29, 2004
SOLVING THE MYSTERY OF THE DANCER MICE, AND CLEFT LIP TOO
By watching mice “dance” and comparing the DNA of the dancers
to their flat-footed siblings, scientists have discovered a genetic cause
of cleft lip and palate in mice, a finding that is already being used
to search for a similar genetic defect in humans. A team led by Rulang
Jiang of the Center for Oral Biology found that a gene known as Tbx10
is responsible for causing cleft lip and palate in mice. The team studied
mice that naturally carry a genetic mutation called Dancer, so named because
mice with one copy of the Dancer mutation twist as they walk, toss their
heads abnormally, and have balance problems due to inner-ear damage caused
by the mutation. For more than 35 years it’s been known that these
mice are also more susceptible than normal mice to being born with cleft
lip and palate, while mice with two copies of the mutation are always
born with the defect. To narrow down the stretch of DNA where the genetic
defect resides, graduate student Jeffrey Bush bred many litters of mice
and monitored the offspring for head-tossing and other Dancer signs. Through
meticulous analysis of the genetics of the dancers vs. the non-dancers,
Bush, Jiang, and Research Professor Yu Lan found the precise genetic defect
responsible for the Dancer mice: They discovered a chunk of genetic material
from another gene – a specialized strip of DNA responsible for turning
a gene on – embedded into the DNA of a gene known as Tbx10, which
encodes one of a family of proteins known to be crucial in development.
The group reported its results this week in the on-line edition of the
Proceedings of the National Academy of Sciences.
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story
ANOTHER WEAPON FOR BEATING CANCER: EXERCISE
Doctors have known for quite awhile that exercise plays a role in preventing
some cancers. But in a new twist, a researcher at the James P. Wilmot
Cancer Center is studying whether exercise provides therapeutic benefits,
such as easing fatigue during radiation treatments. “Cancer patients
historically were told, and often still are told, to go home, relax, don’t
overdo it,” explains Karen Mustian, one of the few scientifically
trained exercise psychologists with a specialty in cancer in the United
States. “However, we are beginning to see that change, just as it
did years ago in cardiology. Individuals who suffer heart attacks today
are placed into a formal exercise rehabilitation program as part of their
recovery. I think we will find that exercise also helps improve the physical
and mental well-being of cancer survivors, and in fact an exercise program
for cancer survivors may become the norm of the future.” Mustian
has launched a pilot study to find out if moderate exercise helps alleviate
the fatigue common among individuals with breast and prostate cancer,
while they are receiving radiation treatments. In addition, Mustian is
working with Wilmot Cancer Center doctors to explore ways to use exercise
as therapy for metastatic breast cancer patients. During informal focus
group sessions with 40 breast cancer survivors, the women told Mustian
that the more active they were, the faster their lives returned to normal
and the better they felt about themselves.
Full
story
ANTHRAX VACCINE RESEARCH STUDY BEGINS IN ROCHESTER
Scientists in Rochester and 11 other cities around the nation are beginning
tests of an experimental vaccine aimed at protecting people against anthrax,
a disease that, like smallpox, has become more threatening with the emergence
of bioterrorism. For most of modern history anthrax has been a rare disease
in people; it’s most likely to infect farmers, veterinarians, and
people who work with animals or animal products. That all changed more
than two years ago, when several envelopes containing anthrax spores that
bore the hallmark of sophisticated processing were mailed, emptying several
office buildings, infecting several people, and spurring the search for
a better vaccine. While an anthrax vaccine now exists and is used primarily
to protect military personnel, it requires a cumbersome routine –
six shots over 18 months, with a booster shot every year thereafter –
for the vaccine to confer protection. The current vaccine also causes
severe side effects. “If you’re trying to immunize in the
face of a threat, particularly if the infectious agent has already been
released, a delay of 18 months until the vaccine is effective is a big
problem,” says John Treanor, professor of medicine and director
of the Vaccine and Treatment Evaluation Unit. “That’s just
too long to wait.” Scientists are trying to develop a vaccine that
works faster, with fewer shots and no annual booster, with fewer side
effects.
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