Prospective studies have shown that the frequency of gastrointestinal symptoms may be as high as 70% in children with ASD; the majority showing inflammation of the ileum and/or colon. Gene expression profiling studies have suggested that the inflammation in the intestines of GI symptomatic ASD children may represent a unique type of bowel disease, one that is different from both Crohn’s disease and ulcerative colitis yet shares many of the molecular features of these conventional IBDs. Anecdotal reports suggest that treating underlying intestinal inflammation improves the quality of life of these children and their families and, in some cases, improves core autism features such as behavior and cognition.
Gene expression profiling in bowel biopsy tissue is an important step in our understanding of autism as the data are derived from pathologically affected tissue. In our study, once the intestinal tissue gene expression profile is established we will seek to determine which of those same markers are present in peripheral blood as well. This will provide an objective and accurate blood test to aid in the diagnosis of ASD-associated inflammatory bowel disease (IBD) and may perhaps preclude the need to perform invasive and expensive ileocolonoscopies. Identification of such markers will also provide important information as to which genes are being “turned on” and “turned off” in patients with ASD-associated IBD thus providing potential targets for treatment of the bowel disease.