NEW YORK, Oct 25 (Reuters Health) --
Genetic mutations in the enzyme that processes folic acid may protect
against a particular type of leukemia, researchers report.
The findings also suggest that a deficiency in folic acid may play a
role in the development of this type of leukemia, namely acute lymphocytic
leukemia. For the estimated two-thirds of the population that does not
have one of the mutations, however, the study results highlight the need
to consume foods rich in folate, such as leafy green vegetables, fruits
and orange juice, one of the study's authors told Reuters Health in an
interview.
Adequate consumption of folate is known to prevent some birth defects
affecting the backbone and spinal cord, but research has also suggested
that people with certain genetic mutations that affect the processing of
folic acid may be less likely to develop colon cancer, according to Martyn
T. Smith, of the University of California, Berkeley, and colleagues. This
type of mutation slows down the breakdown of folic acid so that more of
the nutrient remains available in the body.
To see if the mutations also offered protection against leukemia, the
researchers studied 308 adults with leukemia and 491 people of the same
age and sex who did not have cancer. The investigators analyzed blood
samples from all participants to see whether they had mutations in the
gene for the enzyme that processes folic acid.
Having one or more of the mutations did not appear to offer any
protection against the most common type of leukemia in adults, acute
myeloid leukemia, according to the report in the October 26th issue of the
Proceedings of the National Academy of Sciences.
But the mutations did protect against another type of leukemia, acute
lymphocytic leukemia, which accounts for 10% to 15% of leukemia cases in
adults, Smith noted in an interview with Reuters Health. Having one or
more of the mutations lowered the odds of having this type of cancer by 3
to 14 times, the researchers note.
These genetic mutations "will protect you against acute (lymphocytic)
leukemia but not against myeloid leukemia," Smith said in the interview.
Since most people do not have one of the protective mutations, the
findings highlight the importance of "making sure people drink orange
juice and eat their leafy vegetables," Smith said.
The next step is to see whether the mutations offer protection against
leukemia in children, he said. Unlike adults, acute lymphocytic leukemia
is the most common form of the illness in children.
The results of the study suggest that people who do not get enough
folic acid may be putting themselves at risk for one type of leukemia, Dr.
Bruce N. Ames, also of the University of California, Berkeley, writes in
an editorial that accompanies the study.
In his editorial, Ames highlights the importance of studying the effect
of other nutrients on the development of cancer. He notes that the rate of
most types of cancer is nearly twice as high among the quarter of the
population that eats the least fruits and vegetables.
