Hypothetically, genetic targeting of the Kcnj6 gene could affect the expression of adjacent genes. One such gene, the dual specificity tyrosine phosphorylation regulated kinase 1A (Dyrk1A), affects many important phenotypes in DS including cognition and synaptic plasticity (Altafaj et al., 2013; Souchet et al., 2014). To assess if the genetic alterations of Kcnj6 dose affected the expression of Dyrk1A, we compared levels of Dyrk1A protein in hippocampal samples of Kcnj6+/− and Kcnj6+/+ mice (Fig S1). As can be seen from both the representative blots (Fig S1A) and their quantification (Fig S1B), levels of Kir3.2 were reduced proportional to gene dose (p = 0.0003), while levels of Dyrk1A were not altered (p = 0.76) in Kcnj6+− vs. Kcnj6++ mice. Thus, genetic alterations in Kcnj6 dose had no impact on the expression of Dyrk1A.
