MONDAY, June 30 (HealthDay News) -- Researchers have identified
21 new genetic regions implicated in Crohn's disease, bringing to
32 the total number of genes and loci -- regions of the genome
typically including one or more genes that are known to increase
susceptibility to the disease.
For this study, published in the journal
Nature Genetics, the international team of scientists and
clinicians analyzed DNA samples from almost 12,000 people in Europe
and North America.
"We now know of more than 30 genetic regions that affect
susceptibility to Crohn's disease. These explain only about a fifth
of the genetic risk, which implies that there may be hundreds of
genes implicated in the disease, each increasing susceptibility by
a small amount," lead author Dr. Jeffery Barrett, of the Wellcome
Trust Centre for Human Genetics at the University of Oxford, said
in a prepared statement.
"Whilst this study shows the power of genome-wide association
studies to reveal the genetics behind common diseases, it also
highlights the complexity of diseases such as Crohn's," Barrett
noted.
Crohn's disease causes inflammation of the gastrointestinal
tract, resulting in pain, ulcers and diarrhea. Onset of the disease
typically occurs between the ages of 15 and 40, but it can strike
at any age. As many as 80 percent of people with Crohn's disease
will require surgery.
Along with identifying potential new targets for the development
of drugs to treat Crohn's, this study found that loci with genes
associated with Crohn's are also implicated in a number of other
diseases such as asthma, diabetes, rheumatoid arthritis and
psoriasis.
"It's too early for us to say how Crohn's disease and many of
these other diseases, including asthma, are linked at a biological
level," study co-author Dr. Miles Parkes, consultant
gastroenterologist at Addenbrooke's Hospital and the University of
Cambridge, said in a prepared statement. "However, we are building
up a picture of the biology underlying Crohn's disease, and the
more we understand about the underlying biology of these diseases,
the better equipped we will be to treat them."
"Genetics, and particularly the large scale approach of
genome-wide association studies, offers much hope for understanding
the biological causes of complex diseases," Dr. Mark Walport,
director of the Wellcome Trust, said in a prepared statement.
"Studies such as this also highlight the important relationships
between different diseases, and, as such, may offer valuable
insights into the pathways that lead to common symptoms such as
inflammation."
The Wellcome Trust is a charity that funds biomedical
research.
More information
The U.S. National Institute of Diabetes and Digestive and Kidney
Diseases has more about
Crohn's disease.
