Ventral abdominal wall dysmorphogenesis of Msx1/Msx2 double-mutant mice.

Msx1 and Msx2 genes encode the homeodomain transcription factors. Several gene knockout mice and expression studies suggest that they possess functionally redundant roles in embryogenesis. In this study, we revealed that Msx1 and Msx2 were expressed during ventral body wall formation in an overlapping manner. Msx1/Msx2 double-mutant mice displayed embryonic abdominal wall defects with disorganized muscle layers and connective tissues. These findings indicate that Msx1 and Msx2 play roles in concert during embryonic ventral abdominal wall formation.