In order to obtain information pertinent to human and to investigate the potential of developing a porcine model for RDP/AHC, we have cloned the porcine ATP1A1, ATP1A2, and ATP1A3 coding sequences found expressed in brain, and the promoter region of ATP1A3. We report here structural and functional investigations in relation to these genes and the ATP1A3 promoter, as well as the spatial expression pattern in adult pigs and in embryos of different development stages. Here, ATP1A3 is linked to alternating hemiplegia of childhood.