Published on January 2, 2006 at 9:21 PM
But how far can these results be applied to human beings? To answer this question, Dr. Karsak turned to a team of scientists working in France who had access to genetic samples from more than 160 female osteoporosis patients and 240 healthy women. This line of enquiry proved a complete success: "We found that a specific variant of the CB2 gene occurs more frequently among the patients than among the healthy control group," says Dr. Karsak. Individuals who carry this defect in their genetic make-up are not destined to have problems. However, as she points out, "Women with this mutation have a three-fold higher risk of osteoporosis."
The results show not only that the CB2 receptor is essential for the maintenance of a normal bone mass; they also open up completely new possibilities for therapy: "In many women with osteoporosis the CB2 receptor functions, so in their cases the disease has other causes. For them we could consider stimulating the receptor through medication and in this way slow down their bone loss." The possibility that this approach can work has been demonstrated by the experiments on mice without ovaries.
The findings hold out hope for women with a CB2 defect, too. First, it is easy to identify whether a woman is carrying the relevant mutation, so the results promise improved and faster diagnosis. Second, they have drawn attention to a previously unknown regulatory mechanism, making it a focus of osteoporosis research. Here lies the chance of developing new medicines in the long-term.