Kcnk9 (potassium channel, subfamily K, member 9) showed monoallelic maternal expression in whole
mouse embryos, and in adult brain (the only tissue in which expression was detected) (Ruf D et al, 2007).
Kcnk9 is about 260 kb downstream of Peg13 which has a germline maternally-methylated DMR. The
Kcnk9 promoter CpG island was not methylated. Ruf et al conjecture that Kcnk9 is regulated by the