DNA-SEQUENCE REPETITION IN GENOME OF AMERICAN OYSTER

The genome of Crassostrea virginica, the American oyster, was studied by reassociation kinetics in order to construct a profile of DNA sequence frequency components. Oyster DNA was shown to contain at least 51% single copy DNA sequences and 2 classes of middle repetitive DNA. The major repetitive class contains sequences which are repeated on the average 20 times and comprise 28% of oyster DNA. The other class representes 10% of oyster DNA and contains sequences repeated approximately 3000 times. The DNA of oyster contains at least 1% foldback sequences. The spectrum of DNA repetition components in the American osyter is similar to the genomes of other mollusks.