EXTENSIVE GENETIC VARIATION IN MITOCHONDRIAL DNA'S AMONG GEOGRAPHIC POPULATIONS OF THE DEER MOUSE,PEROMYSCUS MANICULATUS

Abstract

Restriction endonucleases have recently permitted the detection of extensive intraspecific mitochondrial DNA (mtDNA) sequence heterogeneity in a number of mammalian species (e.g., Potter et al., 1975; Upholt and Dawid, 1977; Avise et al., 1979b; Brown, 1980; Brown and Simpson, 1981; Ferris et al., 1981). Because mtDNA appears to evolve very rapidly (Brown et al., 1979), and because mtDNA seems to be strictly maternally inherited (Hutchison et al., 1974; Lansman et al., 1983), the molecule has been advocated as a potentially useful marker for estimating matriarchal phylogenies within and among conspecific populations and closely related species (Lansman et al., 1981). To date, however, only a small handful of studies have begun to exploit this potential for natural population analysis (Avise et al., 1979b; Brown and Wright, 1979; Brown, 1980; Brown and Simpson, 1981; Ferris et al., 1981a, 1981b). In the first paper of this series, we included a description of mtDNA restriction fragment divergence among three geographically distant samples of the deer mouse, Peromyscus maniculatus (Avise et al., 1979a). Of particular interest was the observation that samples from Colorado and southern Michigan were very similar in mtDNA sequence (estimated nucleotide divergence, P .005), while a sample from North Carolina was very distinct from these (P .040). Here we greatly extend our survey of the deer mouse by analyzing mtDNA sequence variation in 135 animals collected across much of the vast range of the species in North America. Our procedure has been to map restriction sites recognized by eight endonucleases. restriction maps permit comparisons of the pattern and character of changes in the mtDNA molecule that have occurred during its evolutionary history in P. maniculatus. Thus the data presented in this paper are of considerable significance to two different but closely interrelated aspects of mtDNA evolution: (1) the ' Number IV in the series, The use of restriction endonucleases to measure mitochondrial DNA sequence relatedness in natural populations. 2 Current address: Laboratory of Genetics, National Institute of Environmental Health Sciences, Research Triangle Park; North Carolina 27709.