CD39 and Gene Variant Linked to Crohn's

Saw an article posted yesterday via WebMD about another potential genetic link found to Crohn's Disease. The gene variant, common in white people and those with European descent, causes a lower amount of the enzyme CD39 to be created in the gut. The enzyme dampens inflammation. Here's an excerpt:

All humans have a CD39 gene. But some have a version of the gene linked to lower CD39 levels. Friedman and colleagues identified a genetic marker for low CD39 production. They then looked for this marker in 1,748 patients with Crohn's disease and in 2,936 people without IBD.

They found that the genetic marker was significantly more common in people with Crohn's disease. Moreover, people without IBD were more likely to carry two copies of the high-CD39 gene, while those with Crohn's disease were more likely to carry two copies of the low-CD39 gene.

Genetics are not destiny. Not everyone with the low-CD39 gene has or will have IBD. Even having two copies of the gene only increases a person's risk of Crohn's disease by 27%.

But since about 40% of whites of European ancestry carry at least one copy of the gene, its effects across the entire population should be quite large.

It seems there may be many contributing factors to Crohn's. Perhaps that means it's an umbrella disorder with many possible causes (rather than one single cause).