Figure 1. Human mtDNA structure.

The positions of mtDNA-encoded genes are shown separated according to whether they are encoded by the heavy strand (H-strand) or light strand (L-strand), and the location of the replication origins OriH and OriL are indicated. An enlargement of the non-coding region (NCR, top) shows the location of the three promoters HSP, LSP and LSP2, as well conserved sequence blocks (CSBs) 1, 2 and 3, and 7S DNA, with its 5′ end in the OriH region and its 3′ end at the termination-associated sequence (TAS).