Genomic localization of the investigated markers within the human mitochondrial DNA molecule. The genetic location of mtDNA markers genotyped in the present study is indicated in the inner circle. H and L stand for heavy and light strands, respectively, given the asymmetric distribution of G and C nucleotides, with H being the G-rich strand. The seven complex I subunits (ND1, 2, 3, 4L, 4, 5 and 6), one complex III subunit (Cyt b), three complex IV subunits (COI, COII, and COIII), two complex V subunits (ATPases 6 and 8), two ribosomal RNAs (12S and 16S rRNAs), 22 tRNAs and D-loop regions are shown. Gene products encoded by the L-strand are shown in the inner circle (one letter code) while the products of the H-strand are shown in the outer circle. Arrows indicate the locations of promoters PL and PH for the transcription and replication origin OH. Adapted from MITOMAP .