April 16, 2007 -- Scientists have identified five new DNA regions that may make Crohn's disease more likely.
Those five DNA regions include three known genes (the ATG16L1, PHOX2B, and NCF4 genes), a predicted gene called FAM92B, and a DNA spot located between genes.
The researchers included John Rioux, PhD, of Canada's University de Montreal and the Montreal Heart Institute.
They had previously reported that two other genes -- the CARD15 and IL23R genes -- were associated with Crohn's disease.
In their new study, Rioux and colleagues screened the DNA of about 1,000 people with Crohn's disease and 1,000 without Crohn's disease.
The researchers found that Crohn's disease was associated with the five newly discovered gene regions and with the two previously noted genes.
Those genetic associations were confirmed in two follow-up DNA screenings of other people with and without Crohn's disease.
Further studies are needed to confirm the findings. Ultimately, such research could lead to new Crohn's disease treatments, note the researchers.
The study, published in the advance online edition of Nature Genetics, doesn't blame Crohn's disease entirely on genes.
Inflammatory bowel disease -- including Crohn's disease -- is "complex" and "results from a combination of genetic and nongenetic risk factors," write Rioux and colleagues.