Junk May Contribute to Type 2 Diabetes Risk
It may be relevant to point a finger at junk as a contributor to type 2 diabetes risk, according to a new study appearing in Nature Genetics. Not junk like “clean out the garage” but junk DNA, which are segments of the genome sequence that was believed to have no apparent function.
Is junk DNA really useless?
DNA is the hereditary material in the nucleus of cells, while genes, which are composed of DNA, are the instructions to produce proteins. Only about 2 percent of the DNA is involved in protein coding, which means the vast majority of DNA is noncoding or “junk.”
But recent research has suggested junk DNA segments do perform tasks even though scientists don’t know what they are. That concept includes this latest discovery, in which a scientific team found that some of these junk areas, called regulatory elements, are involved in turning on genes.
The researchers discovered that variations in these noncoding areas may have an important role in type 2 diabetes risk. More specifically, they documented the areas that control gene activity in pancreatic cells that manufacture insulin, that these gene sequences are found in clusters, and that genetic variants associated with the risk of diabetes also are in these clusters.
According to Mark McCarthy, one of the study’s co-authors and a Wellcome Trust Senior Investigator at the University of Oxford, their findings “may point the way to novel ways of treating and preventing” type 2 diabetes.
Other genetic risk factors for type 2 diabetes
Experts have been busy exploring possible genetic influences for the risk of type 2 diabetes, including another new study that looked at disease development among Mexicans and Mexican Americans. The authors reported on a previously undetected gene called SLC16A11 that increases a person’s risk for the disease by 25 to 50 percent.
The gene is present in up to half of people who have recent Native American ancestry. One of the study’s authors noted that their finding represents “one of the strongest genetic risk factors discovered to date.”
In a previous study published by some of the same researchers from the newer research, a team reported on 10 new genes that contribute to the development of type 2 diabetes. The group made their discovery after analyzing DNA from nearly 35,000 individuals with type 2 diabetes and about 115,000 disease-free subjects.
The study’s main investigator was Professor Mark McCarthy, who explained back in 2012 that there were probably many more gene variations to be discovered “with strongest effects on risk of type 2 diabetes. But there are likely to be tens, hundreds, possibly even thousands more genes having smaller and smaller influences” on getting the disease.
The continuing discovery of genetic variations and their impact on development of type 2 diabetes will hopefully lead to new ways to prevent and treat the diabetes epidemic. Beyond the effect of genetics, people with prediabetes and type 2 diabetes can do much to manage and control blood sugar levels with lifestyle changes.
Pasquali L et al. Pancreatic islet enhancer clusters enriched in type 2 diabetes risk-associated variants. Nature Genetics 2014 Jan 12.