A mutation in a single gene may raise one's risk of getting amyotrophic lateral sclerosis (ALS), or Lou Gehrig's disease, by as much as 30 per cent, offering a potential new target for drug research, Dutch scientists said on Sunday.
They said a variant in the DPP6 gene may give rise to ALS in people without a family susceptibility to the untreatable and fatal disease.
Familial ALS, which accounts for 10 per cent of all cases of the disease, has been linked with mutations in a number of other genes. Researchers have had less luck finding a gene associated with non-familial, sporadic ALS, which accounts for 90 per cent of ALS cases.
But researchers at the University Medical Centre Utrecht said a SNP or single-letter change in the genetic code of the DPP6 gene is "consistently and strongly associated with susceptibility to amyotrophic lateral sclerosis in different populations of European ancestry."
The DPP6 gene controls an enzyme found mostly in the brain that has been linked with spinal cord injury in rats.
Leonard van den Berg and a team of researchers used a new approach called a genome-wide association study to comb through the genetic code of 1,700 individuals with the disease, and compared that to the genome of more than 1,900 healthy people.
The samples came from three European populations and recently reported data from ALS patients in the United States.
What they discovered was a single variant in DPP6 that was associated with ALS in each population. This variant increased the risk of getting the disease by about 30 per cent.
The researchers said this is the first genetic risk factor found consistently across many populations.
"Identification of a common variant within DPP6 is an exciting first step in the genetic study of sporadic ALS, and it opens up new avenues for studying the molecular basis of this devastating disease," Dr. van den Berg and colleagues wrote in the journal Nature Genetics.
ALS progressively kills nerve cells that control muscle movements known as motor neurons in the brain and spinal cord. It is sometimes called Lou Gehrig's disease for taking the life of the famous New York Yankees baseball player in 1941.
About 5,600 people in the United States are diagnosed with ALS each year, according to the ALS Association.