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While at work a few days ago I happened to see a book titles "Blood
Groups and Diseases" by Mourant, Kopec, and Domaniewiska-Sobczak, 1978.
So I looked up celiac disease to see what they had so say about it, even
though the book is a little dated. While there is no doubt that they is
an association between certain HLA types and celiac disease, there wasn't
much to be found between celiac disease and blood types. It said "coeliac
disease...show slight and quite non-significant association with Group
O." So, that was the published opinion as of 1978.
Ellen Eagan