Preface/Front Matter

Our understanding of skeletal biology has taken tremendous strides during the past few years. On the one hand, the spectacular recent breakthroughs in developmental biology have led to an understanding of the global rules shaping and positioning the cartilage and bone primordia in the vertebrate embryo. On the other hand, the discovery of key master regulators of the chondrocyte and bone lineage, such as Sox9 and Runx2, as well as the signaling pathways involved in the regulation of the differentiation of these lineages, has provided a much better understanding of these processes. This knowledge led to the elucidation of the molecular etiology of a majority of bone and cartilage genetic diseases. The goal of this book is to provide a comprehensive and up-to-date summary of the field of skeletal biology. This is a large field and due to space limitations, some areas might be covered more extensively than others. However, an attempt was made to cover all stages of skeletal development and patterning, as well as differentiation of cartilage and bone cells. The complex area of bone physiology is discussed in some of the chapters, but is not addressed extensively. This book covers essentially three major themes. The first theme relates to the development and patterning of bone in vertebrates. Several chapters deal with classical model systems that have been used to study bone and cartilage patterning in the vertebrate embryo. Specifically, the limb bud and the rules governing the formation of bone primordia are addressed, as well as the