Mitochondrial DNA evolution in the Nuu-chah-nulth population.

The first 400 base pairs of the mitochondrial DNA (mtDNA) control region were sequenced from 118 stored serum samples that belonged to different social bands of the Nuu-chah-nulth population. The sequences were used to calculate lineage divergence within and between social bands. The divergence values showed that the Nuu-chah-nulth bands were homogeneous, as evidenced by the amount of shared mtDNA lineages between the bands. When the mtDNA lineages were grouped by geographic regions (which also correspond with linguistic division), no relationship could be established. Also, despite the social organization of the Nuu-chah-nulth (matrilocal society), and mating preference (mating within bands) no relationship was found between lineage divergence and bands. Sixty-one polymorphic sites were identified in different regions in the mtDNA molecule from 60 nonrelated Nuu-chah-nulth. The sites were obtained by sequencing methods and by using restriction enzymes. The mtDNA lineages obtained from the different regions were used to estimate phylogenetic trees. Several inconsistencies were noted among the trees. Some of these could be explained by the different rates of evolution inside the mtDNA molecule. Therefore, the conclusion made from phylogenetic analysis should be draw with caution