When calf thymus deoxyribonucleic acid (DNA), propyl gallate (PG) and their five mo-ecular mixtures (with PG content of 1, 2, 5, 10 and 20%) are irradiated with γ-rays indry state in vacuum at 296°K, the ESR spectra of all molecular mixtures differ strikinglyfrom those of DNA, but bear a close resemblance to those of PG. The spin yield in the PGcontained in these mixtures is two to three orders of magnitude higher than that in the caseof PG irradiated separately. Furthermore, on the basis of the relative saturation characteris-tics of ESR spectra, these molecular mixtures behave more like PG than like DNA. It maybe inferred that the radiation-induced spins could be transferred from DNA to PG. Withr representing the molar ratio of nucleotides to PG, we have found a good linear correlationbetween the transfer ratio (TR) and r~(1/2). One PG molecule could protect at least 68 nu-eleotides in the duplex DNA chain, and thereby the minimal range of spin transfer is estimat-ed at 115 ?. Results obtained from irradiation at 77°K show that PG exerts no protectiveeffect on DNA, so DNA sustains an irreversible damage. It is thought that the spin transferfrom DNA to PG is exclusively due to a hydrogen transfer mechanism. We have also demons-trated the transfer of radiation-induced spins from both thermally denatured DNA and TMPto PG. The former process can be ascribed primarily to the hydrogen transfer mechanism,Whereas the latter, as in the case of native DNA, exclusively to this mechanism. When galf thymus deoxyribonucleic acid (DNA), propyl gallate (PG) and their five mo-ecular mixtures (with PG content of 1, 2, 5, 10 and 20%) were irradiated with γ-rays indry state in vacuum at 296 ° K the the ESR spectra of all molecular mixtures differ strikinglyfrom those of DNA, but bear a close resemblance to those of PG. The spin yield in the mixtures of two to three orders of magnitude higher than that in the caseof . Even, on the basis of the relative saturation characteris-tics of ESR spectra, these molecular sounds behave more like PG than like DNA. It may inferred that the radiation-induced spins could be transferred from DNA to PG. Withr representing the molar ratio of nucleotides to PG, we have found a good linear correlation between the transfer ratio (TR) and r ~ (1/2). One PG molecule could protect at least 68 nu-eleotides in the duplex DNA chain, and thus the minimal range of spin transfer is estimat-ed at 115?. Resu lts obtained from irradiation at 77 ° K show that PG exerts no protective effect on DNA, so DNA sustains an irreversible damage. It is thought that the spin transfer from DNA to PG is due to to hydrogen transfer mechanism. We have also demons-trated the transfer of radiation-induced spins from both thermally denatured DNA and TMPto PG. The former process can be ascribed to to hydrogen transfer mechanism, Whereas the latter, as in the case of native DNA, exclusively to this mechanism.