DNA fingerprints from hypervariable mitochondrial genotypes

Conventional surveys of restriction-fragment polymorphisms in mitochondrialDNA of menhaden fish (Brevoortia tyrannus/patronus complex) and chuckwallalizards (Sauromalus obesus) revealed exceptionally high levels of geneticvariation, attributable to differences in mtDNA size as well as inrestriction sites. The observed probabilities that any two randomly drawnindividuals differed detectably in mtDNA genotype were 0.998 and 0.983 inthe two species, respectively. Thus, the variable gel profiles providedunique mtDNA "fingerprints" for most conspecific animals assayed. mtDNAfingerprints differ from nuclear DNA fingerprints in several empiricalrespects and should find special application in the genetic assessment ofmaternity.