HCN1 and type 2 diabetes mellitus: Additionally, we identified 13 T2D associated genes out of 257 from the T2D knowledge portal database 37 that were enriched in hypothalamic neurons namely ACVR1C, ADCY5, DGKB, DGKG, GLP1R, GNG4, POMC, RASGRP1, SCN3A, HCN1, ITPKA, KSR2, and NRXN3 (Fig. 4E and 4F).