Reconstructed mtDNA tree of the completely sequenced representatives of the major Tibetan mtDNA lineages. Suffixes “A,” “C,” “G,” and “T” refer to transversions, “d” denotes deletion, and “+” indicates an insertion event (without specifying the number of inserted nucleotides). Suffixes “Y” and “R” denote heteroplasmic mutations (C/T and A/G, respectively); recurrent mutations are underlined; “@” denotes a reverse mutation; “s” means synonymous and “ns” means nonsynonymous mutation; “−nc” refers to mutations at the intergenic noncoding regions in segments 577–16023; and “∼r” and “∼t” denote mutations in rRNA genes and tRNA genes, respectively. The C stretch length polymorphism in region 303–315 was disregarded for the tree reconstruction. Suffixes “MT#,” “MI#,” “QPK#,” and “PS#” next to the sample names refer to the sources Tanaka et al. (38), Ingman et al. (39), Kong et al. (19, 24), and Soares et al. (40), respectively. Codes “N,” “R,” “Q,” “Y,” and “G” refer to sampling locations (Nakchu, Shigatse, Qinghai, Yunnan, and Gansu, respectively) of different regional Tibetan populations.