Gene expression analyses for osteoporosis research

Gene expression describes the process of converting the information encoded in the genome into functional gene products like proteins or functional RNAs in the case of non coding RNA genes. Gene expression analysis seeks to identify those genes that are expressed and the level at which they are expressed under certain circumstances. As changes of gene expression are associated with both physiological and pathological processes, gene expression analysis provides a powerful tool to understand the molecular basis of biological processes like cellular differentiation, aging or adaptive responses to the environment and to provide a comprehensive understanding of the molecular basis of complex diseases. In the field of osteology, gene expression analysis has contributed substantially to novel insights into fundamental processes like osteoblast and osteoclast differentiation, bone formation and mineralization, and to novel insights into molecular changes occurring in complex diseases such as osteoporosis or rheumatoid arthritis. This review is aimed at giving an overview on the different techniques available to quantify gene expression and its application in osteoporosis research.