Conformational mutation in human mtDNA detected by direct sequencing of enzymatically amplified DNA.
Restriction enzyme analysis of 241 human mtDNAs revealed polymorphism in the electrophoretic mobility of a fragment corresponding to part of the ND4 gene. Enzymatic amplification and direct sequencing of this fragment demonstrates that a single T--C transition correlates with the faster mobility exhibited by the fragment in seven mtDNAs from Papua New Guinea. The enhanced mobility caused by this transition could result from disrupting an AT-rich region near the middle of the fragment that might make it curve. An analogous mutation at an adjacent position in a European mtDNA causes a similar but more pronounced alteration in mobility. The seven New Guineans with this substitution are all from the Eastern Highlands Province and constitute one clade in a genealogical tree based upon restriction analysis. The additional information provided by sequencing allows refinement of the genealogical tree but does not require modification of higher order branching structure.
Vigilant
L
L
Department of Biochemistry, University of California, Berkeley 94720.
Stoneking
M
M
Wilson
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AC
D001483:Base Sequence; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000032:analysis*; D005784:Gene Amplification; D009154:Mutation; D009690:Nucleic Acid Conformation; D011110:Polymorphism, Genetic
D004272:DNA, Mitochondrial; D004262:DNA Restriction Enzymes