Who'd have thought that a peculiar Chinese dog might shed light on human inflammatory disease? In studying Shar-Pei dogs, Swedish geneticists found that the genes responsible for its distinctive wrinkles also cause an increased risk of periodic fever disorder. The more copies of the gene, the greater the risk, scientists found.
Familial Shar-Pei fever (FSF) causes not only fevers, but swelling of the dogs' ankle joints. Chronic inflammation from the disorder can lead to organ failure and premature death. The study published in PLoS Genetics found that DNA near the hyaluronan synthase 2 (HAS2) gene--which, when overactivated, can cause an excess of the disaccharide polymer hyaluronan--had been duplicated in dogs with FSF. The dogs at greatest risk of FSF had multiple duplications of that DNA segment.
Linking hyaluronan to inflammation and fever could offer clues to periodic fevers and inflammatory disorders in humans, the researchers said. "The finding that hyaluronan is a major trigger of fever opens a new research field in canine and human inflammatory disease," said senior author Kerstin Lindblad-Toh, a professor in comparative genomics at Uppsala University.