I have one of the genes for Celiac Disease and am Gluten Sensitive. I also cannot eat oats. I started getting symptoms from oats long before any hint of problems with gluten. Apparently, one of the Celiac genes can have a separate but equally severe reaction specifically to some protein in oats. It's possible also to be allergic to oats and not other grains, so it may not even be a gluten issue.
Oats themselves don't have the same gluten that wheat/rye/barley do, but because of cross contamination, that's why people with Celiac Disease usually have to avoid oats too (in the U.S.; European countries apparently are better at keeping the cross contamination under control).
I hope this helps - take care,
Gluten & Sulfite Sensitivity, Multiple Food & Inhalant & Medication Allergies, Asthma, Gut issues (dysmotility, non-specific inflammation), UCTD (Lupus?), Osteoporosis, Anemia, Very Low Lymphocyte Counts (T-Cells & B-Cells), malabsorption/malnutrition, etc.
Meds: Pulmicort, Injectable Vitamin B12, Herbs, Nutritional Supplements, Essential Oils, Homeopathy.