The diaphragmatic hernia found in the 8p23.1 deletion syndrome has not been found in the 8p23.1 duplication syndrome to date. The duplication may be associated with copy number changes of the adjacent olfactory receptor/defensin repeats (ORDRs) that predispose to the 8p23.1 deletion and duplication syndromes. High total copy numbers of these repeats have been associated with predisposition to psoriasis and low copy number with predisposition to Crohns disease. Genetics
The duplication includes ~3.75 Mb between the distal and proximal ORDRs at either end of band 8p23.1. The copy number of the adjacent repeats may also be altered. The 8p23.1 duplication syndrome cannot be distinguished using conventional cytogenetics from high level copy number variation of the repeats themselves.Both de novo cases and families with transmitted duplications from parents of both sex are known. The duplication is believed to arise de novo as a result of non-allelic homologous recombination (NAHR) between the proximal and distal ORDRs. NAHR is also thought to give rise to the reciprocal microdeletion syndrome, the polymorphic inversion between the ORDRs and a variety of other large scale abnormalities involving the short arm of chromosome 8. Diagnosis
Phenotypes
See also
Chromosome 8 (human)

References
External links

DECIPHER database description
Autoimmune enteropathy (AIE) is a rare disorder of the immune system that affects infants, young children and (rarely) adults causing severe diarrhea, vomiting, and other morbidities of the digestive tract. AIE causes malabsorption of food, vitamins, and minerals often necessitating replacement fluids and total parenteral nutrition. Some disorders, such as IPEX syndrome, include autoimmune enteropathy as well as autoimmune "pathies" of the skin,  thyroid,  other glands, or kidneys. Symptoms
The main symptoms of AIE include:

Diarrhea (frequent loss of fluids)
Intestinal inflammation
Vomiting
Intestinal bleeding
Difficulty or inability to gain weight
Rapid weight loss
Decreased urine output from dehydration

Diagnosis
There is a diagnostic test for AIE that looks for an antibody against the enterocyte. The diagnostic test contains the Western Blot which can identify the antibody IgG or IgA and with the immunohistochemistry can localize these antibodies. Endoscopy with biopsies of the colon, small colon, stomach, and other locations may be helpful in diagnosing. This test is done to look at the stomach and small intestines and to see what cells are infiltrating the digestive tract. There are also documented cases of autoimmune enteropathy where the auto-antibodies were undetectable and the diagnosis was made on the basis of clinical presentation and response to treatment. Types
There are 3 types of autoimmune enteropathy:Type 1: IPEX syndrome: Immune dysregulation, Polyendocrinopathy, Enteropathy, X – linked 
	syndrome, which is caused by a mutation in the FOXP3 gene. This can only affect boys. Type 2: IPEX-like, which manifests similarly to IPEX syndrome but without recognizable mutations in the FOXP3 gene.