British scientists have identified more than 200 gene locations associated with Crohn's disease, an incurable digestive disorder. Their research utilized the entire human genome, the complete set of human genetic information stored in DNA.
The total is larger than the number of genes located for any other disease, according to ScienceDaily. For example, there are 66 known locations for type 2 diabetes.
The researchers, from University College London (UCL), believe that their findings will eventually lead to more personalized Crohn's treatment. The disorder is one of the two principal types of inflammatory bowel disease (IBD). The other is ulcerative colitis. The Crohn's & Colitis Foundation of America states that Crohn's affects up to 700,000 Americans. It typically strikes between 15 and 35, but can occur at any age.
The exact cause of the disorder has eluded researchers for decades. Most experts believe that several factors play important roles in the development of the disease. Those cited most often are genetics, environmental factors, and an abnormal immune reaction to benign substances like bacteria in the intestines. Crohn's is a chronic illness that can involve any part of the digestive tract from mouth to anus, according to PubMed Health.
Scientists have believed for years that understanding the genetic component of such a complex disease is critical to explaining symptoms and developing better methods of treatment. However, they have remained stymied over detailed genetic mapping for the disorder because of the large number of genes involved, complex interactions with the environment, and a wide range of symptoms.
The British team utilized data from a consortium with information on nearly 1,700 Crohn's patients. Data provided by the U.S. National Institute of Diabetes and Digestive and Kidney Diseases on 813 patients led to replication of results of the British study.
Results from the UCL study appeared in the American Journal of Human Genetics. One of the factors the team believes was responsible for their success was use of highly detailed maps of the human genome. Another was their ability to subdivide Crohn's patients by the way they presented with the disorder. The results also represent the first definite signs that certain patient sub-groups are predisposed to carry different risk genes.
Like most patients who have had this illness for decades, I often become impatient when I read about a discovery linked to the genetics of Crohn's disease. Since about 20 percent of patients have a close family member with IBD, years ago, I asked whether I should have my daughter tested.
The doctor and I agreed that it was pointless. Her symptoms were either due to Crohn's or not. Time would tell. From a patient's perspective, what is strikingly different about the identification of more than 200 genes is the hope that it will lead to more personalized treatment, not just more data on a library shelf.
Vonda J. Sines has published thousands of print and online health and medical articles. She specializes in diseases and other conditions that affect the quality of life.
- inflammatory bowel disease