[Stability of physico-chemical parameters of DNA during long-term storage].

DNA was extracted from calf thymus and sturgeon milt and purified of admixtures; this highly polymeric DNA was studied under conditions of its prolonged storage (for 1 1/2-2 years) at a temperature of 0-4 degrees C in 1 M NaCl in the form of a precipitate under a 70% ethanol and in the lyophilized state. It appeared that DNA obtained from the mentioned sources could be stored for at least 1 1/2 years under the said conditions without any significant damage of its polymeric properties or secondary structure. Although DNA from sturgeon milt had the initial physico-chemical indices similar to those of the thymus DNA, the former displayed much greater stability under the same storage condition, indicating stability of its molecular structure.