Hope for osteoporosis genetic test

A genetic test that identifies women at risk of developing osteoporosis could soon be available, the Daily Telegraph reports. Icelandic firm deCODE published a study last year, which suggested that certain variations in a gene called BMP2 could triple the risk of the bone-weakening disease. Now the Reykjavik-based company plans to market a test that detects these gene variants, which will be available later this year in the US. Chief executive Kari Stefansson announced the news at a meeting held at the Royal Society in London.

Osteoporosis is a disease of old age, in which the bones gradually become weaker and more porous (less dense). The disease often remains undetected until a patient falls and fractures their wrist, hip or spine. People with low 'bone mineral density' (BMD) are more likely to develop the disease than those with a higher BMD. The BMP2 gene makes a protein called bone morphogenetic protein-2, which is involved in bone development. The deCODE researchers compared the BMP2 gene sequence in 188 osteoporosis patients with that present in samples from 94 unaffected people. They found that people who inherited one of three particular BMP2 variants were three times more likely to develop the disease.

The scientists stressed that several other genes are also likely to be involved in osteoporosis, and that factors such as exercise, diet and smoking are also crucial. But looking for key genes could help develop new treatments, and also identify people at high risk of the illness, they said. The researchers also said they had confirmed the link between BMP2 and osteoporosis in the Danish population, as well as Iceland, and were carrying out a study of US women. 'This gene makes a growth factor that stimulates the formation of bone. When there's something wrong with it, the peak bone mass you develop before menopause is limited' said Stefansson at the time.

Yesterday, Stefansson said of the link between BMP2 variants and osteoporosis: 'It has been demonstrated convincingly that lifestyle changes have an impact on how a predisposition like this is turned into a disease'. Women who have an increased genetic risk could take preventative measures, such as drug treatments, taking more exercise and eating a diet rich in calcium, it is claimed.

Another study, published by US researchers earlier this year, reported the on the key role of a mouse gene called Alox15 in the regulation of bone density. The scientists, based at the Oregon Health and Sciences University, said their discovery could lead to new therapies for osteoporosis in humans.