Association of bronchopulmonary sequestration with expression of the homeobox protein Hoxb-5.

Bronchopulmonary sequestration (BPS) is caused by the abnormal development of an accessory lung diverticulum from the foregut very early in embryogenesis. The developmental abnormalities seen with BPS suggest that this anomaly is caused by abnormal expression of homeobox genes, which control axial identity and organ-specific patterning during embryogenesis. The authors previously have shown that the homeobox gene Hoxb-5 is necessary for normal airway branching during lung development. The authors now report that BPS is associated with aberrant developmental expression of Hoxb-5 protein, suggesting that this Hox gene is involved in the development of BPS.