Nucleic Acids Research, 1980, Vol. 8, No. 2 279-298
© 1980
Article |
Evidence for nonrandom alterations in a fraction of the highly repetitive DNA of a eukaryote
University of Tennessee-Oak Ridge Graduate School of Biomedical Sciences, and the Biology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA
*To whome correspondence should be send
Received October 18, 1979. Although the DNA of the red crab Gerycm quinquadene has no patent satellites, a large fraction ({small tilde} 40%) is highly repetitive. Treatment of total DNA by Hind III produces fragments comprising 5–6% of the genome. While the sizes of some of these fragments form an arithmetic series based on an 81 bp repeating unit, the amounts of the multimers differ significantly from distributions observed for multimeric series in the DNAs of other eukaryotes. In red crab DNA, the amounts of some of the multimers suggest that they may have undergone as much as four times the divergence as the others. Other data, however, are more compatible with the conclusion that there has been selective amplification of segments of highly repeated DNA which results in the enhanced amount of specific multimers. These results indicate the presence of a nonrandom process in the evolution of the highly repetitive DNA. Selective mutation alone seems insufficient to explain these results.