The diversity present in 5140 human mitochondrial genomes.
We analyzed the current status (as of the end of August 2008) of human mitochondrial genomes deposited in GenBank, amounting to 5140 complete or coding-region sequences, in order to present an overall picture of the diversity present in the mitochondrial DNA of the global human population. To perform this task, we developed mtDNA-GeneSyn, a computer tool that identifies and exhaustedly classifies the diversity present in large genetic data sets. The diversity observed in the 5140 human mitochondrial genomes was compared with all possible transitions and transversions from the standard human mitochondrial reference genome. This comparison showed that tRNA and rRNA secondary structures have a large effect in limiting the diversity of the human mitochondrial sequences, whereas for the protein-coding genes there is a bias toward less variation at the second codon positions. The analysis of the observed amino acid variations showed a tolerance of variations that convert between the amino acids V, I, A, M, and T. This defines a group of amino acids with similar chemical properties that can interconvert by a single transition.
Instituto de Patologia e Imunologia Molecular Universidade do Porto, Porto 4200-465, Portugal.
Luísa
L
Pereira
Fernando
F
Freitas
Verónica
V
Fernandes
Joana B
JB
Pereira
Marta D
MD
Costa
Stephanie
S
Costa
Valdemar
V
Máximo
Vincent
V
Macaulay
Ricardo
R
Rocha
David C
DC
Samuels
D001483:Base Sequence; D004272:DNA, Mitochondrial / Q000235:genetics*; D030541:Databases, Genetic; D014644:Genetic Variation; D015894:Genome, Human; D054629:Genome, Mitochondrial; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012343:RNA, Transfer / Q000235:genetics
D004272:DNA, Mitochondrial; D012343:RNA, Transfer