Can
scientists create gluten-free wheat plants to make bread with?
Writing in the journal PNAS, the Proceedings of the National
Academy of Sciences, a team of scientists concludes that it’s
quite possible.
People
with serious gluten allergies such as celiac disease now have
only one tried-and-true option: swear off all foods containing
wheat, barley and rye. Only that way can they avoid the damage
that gluten exposure wreaks: abdominal pain, nutritional
deficiencies and a progressive flattening of the tiny hairlike
villi in the gut that are needed for the proper digestion of
food.
Avoiding
gluten isn’t easy, and those with the discipline to succeed
deal with a host of restrictions to their diets.
Scientists
have experimented with another tack: sifting through different
varieties of wheat and barley lines that lack, or make a lot
less of, key gluten proteins in their grains. (Gluten is a
complicated mix of proteins that are stored in seeds of wheat,
barley and rye, and only some — not all — of these
proteins trigger the allergic reactions.)
But
though they’ve found varieties that lack some of the
important allergenic proteins, "None of the tested
materials was completely nontoxic for celiac patients and thus
could not be recommended for general consumption," note
authors of the current study.
Those
authors, Shanshan Wen of Washington State University in
Pullman and colleagues, tried a different approach. It hinged
on a key enzyme — one that helps activate a whole set of
genes that make the most problematic gluten proteins. Using a
genetic engineering trick, they knocked out that enzyme. As a
result, the seeds of the wheat they studied had sharply
reduced levels of this set of problem proteins.
The
authors say it’ll take more tinkering before they can create
a line that eliminates the problem proteins entirely while
keeping other non-problem ones in the seeds. But they write
that they have a good chance of doing it and that the
resulting wheat still should make decent bread for baking.
Next
will come testing — in cell cultures, mice and
gluten-sensitive apes.
This isn’t
the only approach to new dietary solutions for celiac disease.
Some scientists, for example, think it might be possible to
develop oral enzyme therapies. These would digest away the
bits of gluten that cause allergic reactions because they aren’t
properly digested in the gut by natural digestive enzymes.
Others
think it might be possible to desensitize celiac patients by
feeding them tiny amounts of gluten and slowly ramping up the
dose, an approach that’s been successful in some clinical
trials, for example, in treating allergies to peanuts or milk.