In research published online Dec. 23, 2012 in the journal Nature Genetics, scientists have found three new and relatively³ rare genetic² variants⁴ that influence insulin production, offering new clues about the genetic factors behind diabetes⁵. "Studying genetic variants -- even rare ones -- helps us learn how genes⁶ affect health and disease," said Karen Mohlke, PhD, one of the study's senior authors and associate professor of genetics at the University of North Carolina School of Medicine. "In this study, we've implicated⁷ new genes as playing a role in insulin processing and secretion⁸（分泌）."

 

The study is also the first time genetic insights have been reported using exome array genotyping, a new tool that is less costly⁹ than genetic sequencing. This analysis allows scientists to quickly screen DNA¹⁰ samples for known variants in specific genes. It is especially helpful for testing variants that are rare.

 

"The exome array allowed us to test a large number of individuals -- in this case, more than 8,000 people -- very efficiently," said Mohlke. "We expect that this type of analysis will be useful for finding low-frequency variants associated with many complex traits, including obesity¹¹ or cancer."

 

The scientists pulled data from a large health study directed by researchers at the University of Eastern Finland. A research team including postdoctoral scientist Jeroen Huyghe at the University of Michigan, Ann Arbor¹² led the statistical¹³ analysis, which integrated genetic data and detailed¹⁴ health records for a sample of 8,229 Finnish males.

 

Diabetes, which affects more than 25 million people in the United States, results from problems with the body's ability to produce or use insulin. Rather than pinpointing¹⁵ one gene¹ behind the disease, scientists believe there are a whole host of genes that interact with health and lifestyle factors to influence a person's chances of getting the disease.

 

The study revealed that certain variants of three genes -- called TBC1D30, KANK1 and PAM -- are associated with abnormal insulin production or processing, even in people without diabetes. The genes may predispose such individuals to developing the disease.

 

As a next step, the researchers plan to continue to investigate how these genes may lead to diabetes. They also expect the results will inspire other scientists to use exome analysis to look at the genetic factors behind other complex diseases.

 

In addition to Mohlke, the study's co-Principal Investigators¹⁶ included Michael Boehnke, PhD, of the University of Michigan, Ann Arbor and Markku Laakso, MD, of the University of Eastern Finland and Kuopio University Hospital.

 

In the U.S., funding for the research came from the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and the National Human Genome Research Institute (NHGRI), components¹⁷ of the National Institutes of Health.

点击收听单词发音