Novel mitochondrial DNA insertion polymorphism and its usefulness for human population studies. 
The frequency of a polymorphic mitochondrial DNA insertion into the nuclear genome was determined for 870 individuals from a geographically diverse set of 20 populations.  The mtDNA insertion frequency varies significantly among populations, having a large GST value (0.178) and high heterozygosity values within populations.  The clinal pattern of increasing frequency of the insertion from Africans through Europeans and Asians to native Americans is striking.  The polymorphism is a new example of insertion-deletion polymorphisms and is a valuable marker for human population and evolutionary studies.