<<Disclaimer: Verify this information before applying it to your situation.>>

I just ran across a interesting side effect of pernicious anemia that will
certainly add to the recent discussion on a possible link between color
blindness and celiac disease.  Although Red-green colorblindness is an
X-linked recessive gene, and has no connection to celiac disease, there is
an unusual type of color blindness involving yellow and blue that may be
present as a symptom of pernicious anemia. pernicious anemia is caused by
inadequate absorption of vitamin B12 .  Janet DeGraw recently posted an
e-mail about this.  This vitamin is normally readily absorbed in the ileum
(the last part of the small intetine leading to the large intestine).  To
be absorbed, the vitamin must combine with intrinsic factor, a protein
produced in the stomach, which then carries the vitamin to the ileum where
it is absorbed into the bloodstream.  So lack of intrinsic factor, or
absorption problems will cause this type of anemia.  Because the liver
stores a large amount of vitamin B12, anemia doesn't develop until 2 -4
years after the body stops absorbing vitamin B12. Since B12 malabsorption
is often associated with celiac disease, this is something we should think
about getting checked every once and a while.  We shouldn't assume that one
good B12 test result after celiac diagnosis means that we never have to
worry about this - Janet didn't start showing any symptoms until one year
of being gluten-free.

I seem to remember a couple of people in the summary on color-blindness
mention some unusual types of colorblindness, so you may want to be tested
for this.

Susan, Huntington Beach, CA