TORONTO — A large-scale international research study, which included Toronto’s Mount Sinai Hospital, recently reported that it has identified 32 genetic factors involved in Crohn’s disease.
Dr. Mark Silverberg, staff gastro-enterologist at Mount Sinai and assistant professor of medicine at the University of Toronto, explained that Crohn’s is a chronic inflammatory disease of the digestive tract that can cause diarrhea, bloody stools, malnutrition and weight loss, fever, fatigue, bloating and pain.
There is no cure, he said in an interview.
Together with ulcerative colitis, a chronic inflammatory disease of the rectum and colon, it is one of several conditions referred to as inflammatory bowel disease (IBD).
Jews are four times more susceptible to IBD than a similar group of non-Jews, Silverberg said.
He said Crohn’s was not much known until the 1930s, when American gastro-enterologists, including Dr. Burrill Bernard Crohn identified it. It is not clear what happened in the 1930s to make it more prevalent.
Over time, Silverberg added, it became evident to the medical and scientific communities that IBD tends to run in families. In fact, he said, “you find people in the same family having either Crohn’s disease or ulcerative colitis.”
Large population studies in North America, Britain, France and Belgium discovered one gene involved in IBD in 2001. In 2007, using technologies and techniques from the Human Genome Project (an international research study that mapped all the genes in the human body), 11 more were found.
Investigators decided to probe further, and, by analyzing more than 3,000 people all over the world, found another 21 genetic factors.
“The next step,” Silverberg explained, “is to look at each of those genes, discover how an individual gets the disease [not everyone in an affected family gets Crohn’s or colitis] and to find what puts people at risk.”
The more genes that are isolated, he said, the more likely you are to find out what is going on, and perhaps to find a therapy.
For instance, he said, we may find that a gene or genes may not recognize the healthy, normal bacteria that are present in each person’s digestive tract and fight against them.
The goal, Silverberg said, is not to find a cure, but rather to find a way to prevent it, such as with vaccination, probiotics or antibiotics.
Silverberg believes that the studies so far have been so successful because “the team of international researchers has worked together for 12 or 13 years. We collaborate with each other. One person may not get all the glory, but we get much better results.”
For more information, contact Mount Sinai Hospital department of gastro-enterology Inflammatory Bowel Disease Group, 416-586-4800, ext. 8349.