Evolution of Shh endoderm enhancers during morphological transition from ventral lungs to dorsal gas bladder

Endodermenhancer MACS1 of Sonic Hedgehogis conserved in animals with lungs. Here, the authors show that mouse without MACS1 has defective laryngeal development, and use phylogenetic analyses to show association of evolutionary lung-gas bladder transition with change of the enhancer.