At the cellular level, NGN2‐induced excitatory neurons with the alternative AUD KCNJ6 haplotype had a significantly higher density of neurites, accompanied by decreased GIRK2 levels (Figure 4, Panel C). 39 Fluorescence in situ hybridization (FISH) for KCNJ6 also showed a decrease in mRNA, consistent with the scRNAseq results. Reduced GIRK2 expression was associated with increased excitability of the cells generated from individuals with AUD both at the level of individual neurons as well as at the network level (Figure 4, Panel C). A 7‐day 20 mM alcohol exposure induced GIRK2 protein and mRNA expression, ameliorating differences in neuronal excitability (Figure 5, Panels A and B). KCNJ6 overexpression alone replicated the effects of alcohol administration on neuronal excitability (Figure 5, Panel C).
