Decode Genetics has reported finding two genetic variants that cause 57 percent of cases of thyroid cancer, says a story in the New York Times. Their paper in Nature Genetics used a GWAS on a population of Icelandic cases to find two common variants, located on chromosomes 9q22.33 and 14q13.3, that are associated with the disease. About 4 percent of the cases were homozygous for both variants, making the estimated risk of developing thyroid cancer almost six times greater than that of noncarriers. While the findings are notable, since only 1,500 of the 35,000 cases annually in the US result in death, "it would probably not be worth screening the whole population for the two new variants, at least not until the cost of genetic tests was substantially reduced," says the article.