A further overlap is provided by the phenotype of Cooks syndrome, which is characterised by terminal deficiency of the digits reminiscent of that in ZLS; this was previously attributed by experimental modelling in mice to misregulation of Kcnj2 (the murine orthologue of KCNJ2), mediated by large duplications located on the telomeric side of KCNJ16/KCNJ2 [59]. The gene discussed is KCNJ2; the disease is Cooks syndrome.