The human gene coding for HCN2, a pacemaker channel of the heart

Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels, underl ying 'pacemaker' currents (I-f/I-h), are involved in pacemaker activity of cardiac sinoatrial node myocytes and central neurons. Several cDNAs derivin g from four different genes were recently identified which code for channel s characterized by six transmembrane domains and a cyclic nucleotide bindin g domain. We report here the identification of the human HCN2 gene and show that its functional expression in a human kidney cell line generates a cur rent with properties similar to the native pacemaker f-channel of the heart . The hHCN2 gene maps to the telomeric region of chromosome 19, band p13.3. This is the first identification of a genetic locus coding for an HCN chan nel. (C) 1999 Elsevier Science B.V. All rights reserved.