The exact cause of Crohn's disease is not known. Research suggests a genetic component to the disease.
If you have a close relative — such as a parent or a sibling — with Crohn's, you are much more likely to develop the disease. The Mayo Clinic states that as many as one in five people with Crohn's have a close family member with the disease.
Though it can be present in any ethnic or racial group, Crohn's disease is more common in Caucasian populations and Jews with eastern European ancestry, also known as Ashkenazi Jews.
The Hebrew University of Jerusalem explains that over the years, Ashkenazim have generally married within their own ranks. This has created a genetic makeup unique to them. This has also led to a greater frequency of diseases with causes that are at least in part the result of genetic factors, such as:
- Gaucher disease
- Bloom syndrome
- idiopathic torsion dystonia
- familial dysautonomia
Since Ashkenazi Jews also have a higher risk for Crohn's, the genetic link is being explored as a possible explanation.
Researchers believe that certain human chromosomes may have a role in determining whether or not someone gets Crohn's disease. Chromosomes are found within cell nuclei. They’re tightly bound packages of the genetic material that provide instructions for how an organism functions. Humans have 23 pairs of chromosomes in their cells. These are inherited from your mother and your father.
There can be variations in these chromosomes. Sometimes a variation can cause a problem in the function of your body, or at least increase the risk of a problem.
Crohn’s disease is related to chromosome 5 and chromosome 10. Chromosome 5 is one of the largest human chromosomes. Chromosome 10 plays a role in the body's immune response. In addition, researchers have identified 32 gene mutations (changes) that are more common in people with Crohn’s disease.
Since the disease tends to be more prevalent among urban populations, environmental factors such as pollution, diet, or undiscovered bacteria or viruses may be factors as well.
“There is increasing evidence that genetics play a relatively large role in the development of Crohn’s Disease,” states Dr. Charles T. Richardson, a gastroenterologist with Baylor University Medical Center in Dallas, Texas.