Diabetes appears to be written into some people's genes, but with the right diet and exercise, the disease may never surface, according to a new study. Nearly 1 in 10 U.S. adults age 20 and older have diabetes, a condition in which the body cannot properly regulate blood glucose levels, leading to organ disease and other complications. Type 2 diabetes accounts for 90% to 95% of all diabetes cases, and over the past 6 years, researchers have linked a handful of genes to the disease. Most recently a team at deCode Genetics in Reykjavik, Iceland, found that individuals with one...