INADEQUATE PAX-1 GENE-EXPRESSION AS A CAUSE OF AGENESIS OF THE THORACOLUMBAR SPINE WITH FAILURE OF SEGMENTATION - CASE-REPORT

An unusual case with absence and ''fusion'' of several thoracic and lu mbar vertebral bodies leading to a severe thoracolumbar kyphos is pres ented. Late-onset neurological deterioration occurred due to spinal co rd compression, which was treated with anterior decompression. Althoug h several mechanisms for the development of these extensive and rare a bnormalities have been proposed, the cause in humans remains unknown. An embryological basis is presented in the light of recent advances in molecular genetics, which show that abnormal notochordal signals and Pax-1 gene expression can produce an experimental phenotype very simil ar to the one in the patient described here. Thus it is suggested that faults in these early developmental processes may be, at least in par t, responsible far the development of such extensive anomalies.