New gene offers hope for preventive medicine against fractures

The international study, which involved more than 50 researchers from Europe, North America and Australia and was led by Associate Professor Mattias Lorentzon and Professor Claes Ohlsson at the Sahlgrenska Academy, University of Gothenburg, is based on extensive genetic analyses of the genetic material of 10,000 patients and experimental studies in mice.

Through the combined studies, researchers have succeeded in identifying a special gene, Wnt16, with a strong link to bone density and so-called cortical bone thickness, which is decisive to bone strength.

The genetic variation studied by the international research network could predict, for example, the risk of a forearm fracture in a large patient group of older women.

“In the experimental study, we could then establish that the gene had a crucial effect on the thickness and density of the femur. In mice without the Wnt16 gene, the strength of the femur was up to 61 per cent lower,” according to Mattias Lorentzon at the Institute of Medicine, the Sahlgrenska Academy, University of Gothenburg.

The discovery opens up opportunities to develop new medicines to prevent the most common fractures.

“Low cortical bone mass is a decisive factor in, for example, hip and forearm fractures. Unfortunately, the treatments currently used for brittleness of the bones have very little effect on the cortical bone mass,” says Mattias Lorentzon.

“If we can learn to stimulate the signaling routes of the Wnt16 gene, we could strengthen the skeleton in these parts too, thereby preventing the most common and serious fractures. The discovery of Wnt16 and its regulation of cortical bone mass is therefore very important,” according to Mattias Lorentzon.
The article “WNT16 influences Bone Mineral Density, Cortical Bone Thickness, Bone Strength and Osteoporotic Fracture Risk” was published in PLoS Genetics on 5 July.

FACTS ABOUT BRITTLENESS OF THE BONE
Brittleness of the bone, or osteoporosis, is a widespread disease: fractures from brittleness of the bone affects one in every two Swedish women and one in every five Swedish men at some stage in their life.
In all, brittleness of the bone causes 70,000 fractures in Sweden every year, costing the health service approx 5 billion Swedish crowns. Of the fractures suffered by Swedes, 18,000 are hip fractures, which often lead to functional impairment and much suffering as well as a significant increase in mortality among the patients.

Contact:
Mattias Lorentzon, Associate Professor in Endocrinology at the Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, and active at the Center for Bone and Arthritis Research
+46 (0)31-342 49 29
mattias.lorentzon @medic.gu.se