Behcet's disease

Causes of Behcet's disease

The exact cause of Behcet’s disease is unknown, but there is some evidence that both genetic and environmental factors are involved.

Genetic predisposition

The general theory about the cause of Behcet’s disease is that certain people are born with genes that make them more vulnerable to an, as yet unidentified, environmental factor, such as a virus or specific type of bacteria.

If the person is exposed to the environmental factor, something that they have inherited in the genes triggers a malfunction somewhere in their body. Most experts believe that the malfunction occurs in the immune system, causing the body to attack healthy tissue.

The scientific evidence for the genetic basis for Behcet’s disease lies in the fact that a large number of people who have developed the condition also had a specific type of gene, known as HLA B51.

Unknown environmental factor

The evidence of a possible environmental factor being involved in Behcet’s disease is that ethnic groups who are known to be at risk of developing the condition can reduce the risk by leaving their native country.

For example, rates of Behcet’s disease in immigrant Turkish communities are significantly lower than among native Turks.

Some environmental factors that have been suggested as possibly being associated with Behcet’s disease include:

  • the herpes virus,
  • the hepatitis virus,
  • bacteria, and
  • pollutants, such as industrial waste or chemicals.


Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.  
Immune system
The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.
Genetic is a term that refers to genes- the characteristics inherited from a family member.
Last updated: 04 October 2011

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