[Content of 5-methylcytosine in DNA fractions in normal human leukocytes and in chronic leukoses].

A procedure is described for fractionation of DNA obtained from leukocyte lysates of healthy donors and of patients with chronic leukoses using silica gel column chromatography. Lymphocytes and granulocytes of healthy donors as well as leukocytes from patients with chronic lympho- and myeloleukosis were dissimilar in the fractional composition of DNA. Nucleotide composition was studied; content of the DNA I fraction varied distinctly both in healthy donor granulocytes and in leukocytes of patients with chronic myeloleukosis as well as in leukocytes of patients with chronic lympho- and myeloleukosis. All the DNA fractions from leukocytes of healthy donors and of patients with chronic leukoses were dissimilar also in content of 5-methylcytosine.