EcoRI cleavage site variants of mitochondrial DNA molecules from rats.

Abstract

The mitochondrial DNA (mtDNA) molecules of some rats obtained from the SASCO colony contain 6 EcoRI-sensitive sites while the mtDNA molecules of other rats obtained from the same source contain only 4 EcoRI sites. By mapping the positions of the EcoRI sites on the molecules relative the the D-loop it was determined that mtDNA molecules from all rats have 4 EcoRI sites in common, but all the mtDNA molecules of some rats have 2 extra EcoRI sites. EcoRI sensitivity of mtDNA molecules was shown to be maternally inherited. Construction of heteroduplex molecules failed to reveal evidence of gross nucleotide sequence changes associated with differences in EcoRI sensitivity.