HOXB5 and pregnancy disorder: Congenital pulmonary airway malformation is an embryogenesis disorder with an incidence of 0.94 for every 10,000 live births per year.6 Although the biological facts behind this congenital malformation are not clear, multiple mechanisms have been proposed to explain CPAMs, such as exaggerated FGF10 signaling and HOXB5 gene problems.4, 8