Genetic and environmental interaction in malformation of the vertebral column

Congenital vertebral defects occur with an incidence of 0.5-1 per 1000 live births, and can arise from incorrect formation of the vertebral precursors during early embryogenesis (dysostoses), or from ongoing abnormalities of bone and/or cartilage formation during pre- and postnatal life (dysplasias). Much progress has been made over the last 13 years into understanding the genetic etiologies of many cases of congenital vertebral defects. In particular, many vertebral dysostoses are caused by mutation of components of the Notch signaling pathway; whereas vertebral dysplasias may be caused by mutations in components of other signaling pathways. In addition to genetic causes, for the past 200 years experimental and epidemiological evidence has been accumulating that perturbation of the environment of the developing embryo can also result in vertebral defects. Of course neither genetic nor environmental factors are likely to act in isolation, and the interaction of these factors is likely to affect the penetrance and expressivity of vertebral defects. Recently we have uncovered the first mechanistic insights into how the interaction of genetic and environmental factors can increase the incidence and severity of congenital vertebral defects.