Methylation of mouse liver DNA studied by means of the restriction enzymes msp I and hpa II

Science  09 Mar 1979:
Vol. 203, Issue 4384, pp. 1019-1021
DOI: 10.1126/science.424726


The restriction enzymes Hpa II and Msp I both recognize the sequence 5'-CCGG (C, cytosine; G, guanine). However, Hpa II cuts mouse liver DNA to fragments four times larger than does Msp I. The size of DNA cut by Msp I is close to that predicted from base composition and nearest neighbor analysis. The most probable explanation of these results is that in mouse the site 5'-CCGG is highly methylated.