Gliadin can be broken down into various amino acid lengths or peptides. Gliadorphin is a 7 amino acid long peptide: Tyr-Pro-Gln-Pro-Gln-Pro-Phe which forms when the gastrointestinal system is compromised. When digestive enzymes are insufficient to break gliadorphin down into 2-3 amino acid lengths and a compromised intestinal wall allows for the leakage of the entire 7 amino acid long fragment into the blood, glaidorphin can pass through to the brain through circumventricular organs and activate opioid receptors resulting in disrupted brain function.There have been a number of gluten exorphins identified: gluten exorphin A4, A5, B4, B5 and C, and many of them have been hypothesized to play a role in autism, schizophrenia, ADHD and related neurological conditions. In the same way that the celiac iceberg illustrated the illusion that intolerance to wheat is rare, it is possible, even probable, that wheat exerts pharmacological influences on everyone. What distinguishes the schizophrenic or autistic individual from the functional wheat consumer is the degree to which they are affected.
The digestion of gliadin produces a peptide that is 33 amino acids long and is known as 33-mer which has a remarkable homology to the internal sequence of pertactin, the immunodominant sequence in the Bordetella pertussis bacteria (whooping cough). Pertactin is considered a highly immunogenic virulence factor, and is used in vaccines to amplify the adaptive immune response. It is possible the immune system may confuse this 33-mer with a pathogen resulting in either or both a cell-mediated and adaptive immune response against Self.