Strain‐specific hyperkyphosis and megaesophagus in Add1 null mice

The three adducin proteins (α, β, and γ) share extensive sequence, structural, and functional homology. Heterodimers of α‐ and β‐adducin are vital components of the red cell membrane skeleton, which is required to maintain red cell elasticity and structural integrity. In addition to anemia, targeted deletion of the α‐adducin gene (Add1) reveals unexpected, strain‐dependentnon‐erythroid phenotypes. On an inbred 129 genetic background, Add1 null mice show abnormal inward curvature of the cervicothoracic spine with complete penetrance. More surprisingly, a subset of 129‐Add1 null mice develop severe megaesophagus, while examination of peripheral nerves reveals a reduced number of axons in 129‐Add1 null mice at four months of age. These unforeseen phenotypes, described here, reveal new functions for adducin and provide new models of mammalian disease. genesis 50:882–891, 2012. © 2012 Wiley Periodicals, Inc.