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Cuts can induce cancerous tumors
By Laura Sanders
The slightest cut can cause cancerous
cells to crawl to the wound and form
tumors in cancer-prone mice. The new
finding may explain why certain kinds
of cancers seem to cluster around burns,
surgical scars and other injuries.
“This work says that if you have a predisposition to getting cancer, wounding
might enhance the chance that it will
develop,” says cell biologist Anthony
Oro of the Stanford University School
of Medicine.
Epidemiologists have tied a variety
of human cancers to wounds, including
lung, liver, bone and skin cancers, but the
reason for the link has been unclear. In
the new study, Sunny Wong and Jeremy
Reiter of the University of California,
San Francisco introduced a potentially
cancer-causing genetic mutation into
particular stem cells in mice.
Gene form raises
risk for diabetes
GIP variant may have aided
survival during brief famines
By Tina Hesman Saey
A genetic variation that may increase a
woman’s risk of gestational diabetes is
widespread today because it was actually
beneficial to early agricultural populations, a new study suggests.
Pregnant women who carry two copies of a low-activity form of the gene
GIP have higher blood-glucose levels— a marker of gestational diabetes
risk — Sheau Yu Teddy Hsu of Stanford
University and colleagues report online
February 7 in Diabetes. But when the
gene’s low-activity version first arose
somewhere in Eurasia an estimated 8,100
years ago, that same glucose-boosting
quality may have helped women maintain
their pregnancies during lean times.
The work is important for characterizing how one form of a gene can shape
physiology and how evolution may act
on that gene, says Joshua Akey of the
University of Washington in Seattle.
Hsu and his colleagues have previously
reported evidence that the low-activity
version of the GIP gene emerged about
8,100 years ago and rapidly became part
of the genetic makeup of Eurasians.
Today about half of people of European
descent carry this newer form of GIP,
while 70 percent or more of Asians do.
Only about 5 to 10 percent of Africans
have the new form, Hsu says. “It arose
very fast, so it must have some dramatic
effect on human viability,” he says.
In the study, the researchers tested
whether the low-activity form of the
gene had any effect during pregnancy.
Study coauthor Chia Lin Chang of
Chang Gung University in Taiwan col-
lected blood samples from 123 pregnant
women. The team analyzed blood sugar
concentrations and found that women
with two copies of the new form of the
gene had higher levels than did women
with the ancestral form.
