Is 21st Century Living Responsible for Crohn's Disease?

Genetic factors have been researched extensively, but with the identification of more than 200 genes related to inflammatory bowel disease, it is becoming apparent that the answer isn't purely genetic--there are environmental issues at work. There are still many short-term and chronic conditions that researchers are working to understand, and unfortunately, there are still many lifelong illnesses that are currently without a cure. Some of these, including Crohn’s disease, are in fact becoming more common as researchers continue to work towards a cure.

Though scientists understand how the immune system dysfunction causes the symptoms, and though there are various therapies and medications for treating the symptoms, scientists are unsure of how inflammatory bowel diseases like Crohn’s disease develop. The Centers for Disease Control and Prevention (CDC) recently released a statistic that “an estimated 1-1.3 million people in the United States have some form of IBD, and the number is steadily rising.”

Many researchers are looking at other factors in the hunt for the root of all inflammatory bowel disease. Genetic factors have been researched extensively, but with the identification of more than 200 genes related to inflammatory bowel disease, it is becoming apparent that the answer is not purely genetic. Research now presses on in the direction of environmental and lifestyle factors, with the emphasis on western, industrialized countries, where the problem of inflammatory bowel disease is most prominent.

The role of genetics

In order for researchers to know where to begin to look, certain patterns or trends in the prevalence of the disease have to be identified. Genetics were among the first to be identified as a factor in the development of Crohn’s disease and other inflammatory bowel diseases. One of the trends cited for genetic links was explained by Jeffrey C. Barrett, PhD, who serves as senior group leader from the Wellcome Trust Sanger Institute in Cambridge in the United Kingdom.

Barrett found that identical twins had nearly 10 times as many cases of Crohn’s disease and approximately four times as many cases of ulcerative colitis—another prevalent inflammatory bowel disease—than non-identical twins. This finding seemed to suggest that genetics had a serious role to play in the development of inflammatory bowel diseases, though Barrett admits that the data are not straightforward.

This example and other patterns served merely as the beginning of an investigation into the role that genetics have to play in the development of inflammatory bowel disease. Now, over 200 different genes have been identified as potential risk factors, with continual findings as molecular biology technology becomes more advanced. The identification of certain biological pathways and genetic processes gives researchers a greater understanding of the disease with each discovery.

That being said, researchers remain unable to understand how these biological pathways are interrupted. Many of the identified genes are regulators of the immune system, but scientists cannot see how the genes lead to a dysregulated immune system response. As such, it has been determined at least for now that genes can only partially explain the development of Crohn’s disease, and for the time being, scientists are beginning to look elsewhere.

Read on to learn more about the possible connections between modern living and Crohn's disease.