Congenital heart defects differ following left versus right avian cardiac neural crest ablation

The cardiac neural crest is critical for the normal development of the heart, as its surgical ablation in the chick recapitulates common human congenital heart defects such as 'Common Arterial Trunk' and 'Double Outlet Right Ventricle' (DORV). While left-right asymmetry is known to be important for heart development, little is known about potential asymmetric differences between right and left cardiac neural folds with respect to heart development. Here, through surgical ablation of either left or right cardiac neural crest, we find that right ablation results in more varied and more severe heart defects. Embryos with Common Arterial Trunk and with missing arteries occurred in right-ablated embryos but were not observed in left-ablated embryos; moreover, embryos with DORV and with misalignment of the arteries were more prevalent following right versus left cardiac crest ablation. In addition, survival of right-ablated embryos was lower than left-ablated embryos. Together, these data raise the intriguing possibility that there may be differences in left versus right cardiac neural crest during heart development.