Biallelic loss-of-function variants in KCNJ16 cause renal tubulopathy associated with sensorineural deafness,26 whereas heterozygous variants in KCNJ2 producing dominant-negative effects are responsible for Andersen-Tawil syndrome, characterized by periodic paralysis, cardiac arrhythmias, and dysmorphic features.27 Here, KCNJ2 is linked to cardiac rhythm disease.