Gluten Allergy Mostly in Genes
This gluten allergy, known as
celiac disease, is thought to be inherited to some extent, but the current
study is the largest to date to look at identical and non-identical twins.
By comparing identical twins,
who are genetically the same, to non-identical twins, who share
only the same number of genes as most other
siblings, researchers can help determine how much of an ailment
is genetic and how much is due to a shared environment.
In the new study, the
investigators found that environmental factors have little or no effect on
the digestive disorder, which can cause diarrhea, weight loss, stomach
bloating and damage to the small intestine.
This study provides substantial
evidence for a very strong genetic component in celiac disease. They suggest
that several genes work collectively to cause the disorder. A single missing
or altered gene is probably not to blame.
The findings are based on blood
samples drawn from 47 identical and non-identical twin pairs, where at least
one twin had been diagnosed with celiac disease. Individuals were tested for
antibodies that are specific to the disease.
According to the results,
38% of the twin pairs both had signs of
celiac disease -- 75% of identical twins and 11% of non-identical twins.
In other findings, females who
had an affected twin were 30% more likely than an unaffected male twin to go
on to develop the disease themselves.
A shared environment did not
affect the risk of developing the disease, the study found.
Although some genetic
variations are known to increase the risk of the disease, much searching has
not located a gene that exerts a major affect.
It is more likely that a series
of genetic characteristics which individually exert little effect but which
collectively characterize a large gluten intolerant tribe that is spread
throughout the gluten-consuming world.
Gut April 2002;50:624-628
Celiac disease is a genetic
disease that is a severe form of gluten intolerance that results in
intestinal complications. Gluten is the major allergy protein in wheat,
spelt, barley, rye and oats. A study has suggested that celiac disease is
far more prevalent in the United States than previously believed.
Previous studies have shown
that about 1 in 250 people in Europe had the condition, but it was thought
to affect fewer individuals, about 1 in 5,000 in the United States. However,
newer studies suggest that the prevalence of celiac disease may be as low as
one in 33.
Although full blown celiac
disease may be as high as one in 33, sub-clinical celiac disease is far more
common, especially if one is of Irish or Scottish ancestry.
For most of us wheat is not
our friend and we would be better off avoiding it and replacing it with
vegetables.
Related Articles:
The
Prevalence of Celiac Disease in At-Risk Groups of Children in the United
States
Wheat
Sensitivity (Subclinical Gluten Intolerance) Linked To Miscarriages
How to Prevent Wheat
Intolerance In Your Baby
Eating
Wheat Can Double Risk of Death
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