Gluten intolerance, a disorder that causes gastrointestinal symptoms when you eat foods that contain gluten, can vary considerably in its symptoms. Some forms of gluten intolerance like celiac disease -- the most severe form -- are inherited. Less-severe forms, such as gluten sensitivity, don't necessarily have a genetic component and might not cause severe damage to the intestines, as celiac disease does. Grains such as wheat, barley and rye contain gluten.
Inheritance
Celiac disease is an autoimmune disease, meaning that your immune system attacks your body's tissues and organs. Certain inherited genes are more likely to cause an autoimmune reaction to gluten. Two genes found on the HLA-class II complex, called DQ2 and DQ8, must be present for a person to have celiac disease, according to the University of Chicago Celiac Disease Center. Gluten sensitivity, on the other hand, can occur in people without a family history of the disorder.
Susceptibility
If you have a first-degree relative -- which includes parents, children or siblings -- with celiac disease, you have a one in 22 chance of developing celiac disease at some point, according to the University of Chicago Celiac Disease Center. If you have a second-degree relative -- which includes aunts, uncles, cousins and grandparents -- your risk of developing celiac disease is one in 39.
Testing
Genetic testing can determine whether you have one of the two genes that transmit the susceptibility for celiac disease. While you must have one of the genes to have celiac disease, having the genes doesn't necessarily mean you'll develop the disorder. Only 1 to 4 percent of Americans develop celiac disease, even though 35 percent of Americans carry one of the two genes, the Celiac Disease Center explains. Other genetic or environmental factors probably play a part in determining whether you develop celiac disease, the Genetics Home Reference explains.
Diagnosis
A family history of gluten intolerance and the presence of the genes that can cause the disorder aren't enough to diagnose celiac disease. Your doctor might suggest a biopsy of the cells in the small intestine if he suspects that you have celiac disease. The cells will show damage to the villi, finger-like projections that help you absorb nutrients from the small intestine. If you have gluten sensitivity, the biopsy won't show this type of destruction of the villi.
