Weak links between candidate gene and osteoporosis

Vertebral compression fractures in a patient with osteoporosis. Image: Stuart Ralston.

Osteoporosis is a complex bone disease hitting one out of every two women and one in eight men over 50. It is characterized by low bone mass and structural deterioration of bone tissue. Osteoporosis is controlled genetic and environmental factors, and there are several candidate genes we think are linked to the development of osteoporosis. One of these genes is called COL1A1, and certain mutations in this gene are known to cause bone-related diseases. Tests were devised to look at the mutations in COL1A1 and correlated them to the incidence of osteoporosis. However, just how strong the link between a particular COL1A1 mutation, called ‘T’ for short, and osteoporosis was debatable.

Now a European study of 24000 people looked provides the answer. Unfortunately, it was found that the T mutation explains only 10% of osteoporosis cases, and therefore is not the great candidate that we thought it was. On top of that, having the T mutation does not translate to a higher number of fractures. However, this does not close the door on other genetic factors, including other mutations in COL1A1. As always, more large-scale studies such as this one are needed to quantify their effects.

The study was the EU-funded Genetic Markers for Osteoporosis (GENOMOS), and its results were published in the Public Library of Science (PLoS) Medicine journal, in paper entitled Large-Scale Evidence for the Effect of the COL1A1 Sp1 Polymorphism on Osteoporosis Outcomes: The GENOMOS Study.

Technorati Tags: osteoporosis, genetics, science, genes