Genetic Traits Celiac Disease

Bread, cereal, pasta, and pizza: most of these delicious foods contain gluten, a family of proteins found in wheat, barley, and rye. If you are one of the millions of people worldwide with celiac disease, gluten can cause severe damage to your small intestine and affect your bodys ability to absorb nutrients. Celiac disease is most common in northern European countries and in the United States. Although there is no cure, it can be managed very successfully through a careful gluten-free diet.

About Celiac Disease

Celiac disease, also known as celiac sprue, nontropical sprue, and gluten-sensitive enteropathy, is a genetic disease of the digestive system brought on by gluten consumption. In a person afflicted with this disorder, gluten triggers an autoimmune response that damages the small intestine. Once the small intestine is damaged, its unable to effectively absorb nutrients from food.

Symptoms of celiac disease are varied. Digestive symptoms are more common in infants and young children and include:

  • abdominal bloating and gas
  • constipation
  • diarrhea
  • pale, foul-smelling stool
  • vomiting
  • weight loss.

Adults may experience digestive and more widespread symptoms:

  • anemia
  • arthritis
  • bone and joint pain
  • canker sores
  • depression and anxiety
  • fatigue
  • infertility
  • skin rash
  • tingling in the hands and feet.

Over 2 million Americans, or about 1 in 133 people, have celiac disease. The disorder is more common in people who have type 1 diabetes, Down syndrome, autoimmune thyroid disease, and microscopic colitis. Nearly 1 in 22 people with a parent, sibling, or child diagnosed with celiac disease may also develop it.

Biology of Celiac Disease

Tiny, hair-like protrusions called villi line your small intestine and are responsible for absorbing nutrients from food. In celiac disease, the villi are damaged, nutrients arent absorbed and you become malnourished as vitamins, minerals, protein, and fat are eliminated in your stool rather than absorbed into your body. If celiac disease is left untreated, the mal-absorption can result in early-onset osteoporosis, iron deficiency anemia, nervous system disorders, cancer, and other conditions.

Genetic Risk of Celiac Disease

Celiac disease is a genetic disorder. In fact, 5 to 15 percent of children and siblings of a person with celiac disease will develop it. So far, scientists have identified certain genes (HLA-DQ2 and DQ8) that are associated with celiac disease. However, the presence of the genes does not indicate that a person will necessarily develop the disease. Rather, they have a genetic susceptibility to it.

Interpreting Your Genetic Test Results

If you get tested and find that you do carry either the DQ2 or DQ8 gene, it does not mean that you will develop celiac disease; it simply means that your genes are compatible with the disorder. Your children can inherit one of these genes from you, so if you or the other parent carries one of the identified genes, your children may be at risk. An estimated 92 to 98 percent of celiac disease patients carry the DQ2 gene and 2 to 8 percent carry the DQ8 gene. However, if you dont carry one of these genes, you can usually rule out celiac disease.

Preventing and Treating Celiac Disease

Since celiac disease is a genetic disease, there is no surefire way to prevent it. The only known preventative method of contracting the disease is avoiding glutens from birth. If you do have celiac disease, adhering to this lifetime gluten-free diet is the only treatment. Avoiding all wheat, barley, and rye will enable your small intestine to heal and most always will allow a complete recovery. Complete intestinal healing usually takes about three to six months in children and can take several years in adults, but most people notice improvement in symptoms after just a few days. Some people, although rare, dont improve on a gluten-free diet due to severe small intestine damage. They may need anti-inflammatory medications and other supplements to treat the mal-absorption.

Results of a 2002 study in the American Journal of Clinical Nutrition indicate that breastfeeding may help to prevent celiac disease in children. Children younger than two years old who were breastfed when they were first introduced to gluten had a 40 percent lower incidence of the disease than children who werent.

Frequently Asked Questions about Celiac Disease and Genetics

Q: What can I eat on a gluten-free diet?

A: You can still eat a very healthy, well-rounded diet. Choose from meat, fish, poultry, fruits and vegetables, rice, potatoes, dairy products, and gluten-free flours (rice, soy, corn, etc.), and make sure to check for hidden sources of gluten in packaged products. As more and more people are diagnosed with celiac disease, plenty of tasty gluten-free options are surfacing.

Q: How can I find out if I have celiac disease?

A: If youre having symptoms of celiac disease, your doctor can do a blood test to check for antibodies. If this is positive, your doctor can confirm the diagnosis with an intestinal biopsy. A DNA test can also test for genes linked to celiac disease.

Q: If Ive always had the genes associated with celiac disease, why did I just start showing symptoms?

A: For unknown reasons, the disease can often be triggered by pregnancy, surgery, childbirth, viral infection, or severe stress.

Recent News on Celiac Disease and Genetics

Beginning in spring 2009, an Australian doctor embarked on Phase 1 of a vaccine trial for celiac disease. Designed to gradually desensitize sufferers to gluten, the vaccine would allow the villi to heal, and gluten-free diets would hopefully be a thing of the past.

Resources

Allan, B. (2009). CeliacdDisease vaccine trial. Retrieved June 29, 2009, from the Medical News Today Web site: http://www.medicalnewstoday.com/articles/145049.php.

Celiac.com. (n.d.). Breast feeding longer could prevent celiac disease. Retrieved June 29, 2009 from the Celiac.com Web site: http://www.celiac.com/articles/573/1/Breast-Feeding-Longer-Could-Prevent-Celiac-Disease/Page1.html.

Celiac Disease Foundation. (n.d.). Celiac disease. Retrieved June 29, 2009, from the Celiac Disease Foundation Web site: http://www.celiac.org/cd-main.php.

Kimball Genetics Inc. (n.d.). Celiac disease DNA test. Retrieved June 29, 2009, from the Kimball Genetics Web site: http://www.kimballgenetics.com/tests-celiacdisease.html.

Lewey, S. (2008). Ten facts about celiac disease genetic testing. Retrieved June 29, 2009 from the Celiac.com Web site: http://www.celiac.com/articles/21567/1/Ten-Facts-About-Celiac-Disease-Genetic-Testing/Page1.html.

Mayo Foundation for Medical Education and Research. (n.d.). Celiac disease. Retrieved June 29, 2009, from the MayoClinic Web site: http://www.mayoclinic.com/health/celiac-disease/DS00319.

National Institute of Diabetes and Digestive and Kidney Diseases. (n.d.). Celiac disease. Retrieved June 29, 2009 from the National Digestive Diseases Information Clearinghouse Web site: http://digestive.niddk.nih.gov/ddiseases/pubs/celiac/#symptoms.