Bones in the arms and legs become weak and brittle in old age often because they are not engaged in as much exercise and bearing of weight as they are in youth. However skull bone, which bears almost no weight throughout life, remains hard and particularly resistant to breaking.
Now the researchers at Queen Mary, University of London have examined the two parts of the skeleton and discovered they very different genetically. They hope that the findings will help them develop ways of stopping hip and wrist bones becoming brittle in old age.
"Everybody thought bones were just bones but they are not," said the lead author, Dr Simon Rawlinson, Lecturer in Oral Biology at Queen Mary, University of London, "But this shows they are very different.This research is exciting because it tells us why our skulls remain so tough as we age compared to the bones in our arms and legs.
“Now we understand this phenomenon better, we also understand osteoporosis better. And this has opened up many new lines of research into how the disease could be treated or even prevented.”
People who develop osteoporosis have fragile bones which are prone to breaking. The condition becomes more common as we age, especially in post-menopausal women when levels of oestrogen fall dramatically. In the over 50s it affects half of all women and a fifth of all men.