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Environ Health Perspect. 1993 October; 101(Suppl 3): 73–77.
PMCID: PMC1521171
Research Article

Indications of repair of radon-induced chromosome damage in human lymphocytes: an adaptive response induced by low doses of X-rays.

Abstract

Naturally occurring radon is a relatively ubiquitous environmental carcinogen to which large numbers of people can be exposed over their lifetimes. The accumulation of radon in homes, therefore, has led to a large program to determine the effects of the densely ionizing alpha particles that are produced when radon decays. In human lymphocytes, low doses of X-rays can decrease the number of chromatid deletions induced by subsequent high doses of clastogens. This has been attributed to the induction of a repair mechanism by the low-dose exposures. Historically, chromosome aberrations induced by radon have been considered to be relatively irreparable. The present experiments, however, show that if human peripheral blood lymphocytes are irradiated with low doses of X-rays (2 cGy) at 48 hr of culture, before being exposed to radon at 72 hr of culture, the yield of chromatid deletions induced by radon is decreased by a factor of two. Furthermore, the numbers of aberrations per cell do not follow a Poisson distribution but are overdispersed, as might be expected because high-linear energy transfer (high LET) alpha particles have a high relative biological effectiveness compared to low-LET radiations such as X-rays or gamma rays. Pretreatment with a low dose of X-rays decreases the overdispersion and leads to a greater proportion of the cells having no aberrations, or lower numbers of aberrations, than is the case in cells exposed to radon alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Full text

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Olivieri G, Bodycote J, Wolff S. Adaptive response of human lymphocytes to low concentrations of radioactive thymidine. Science. 1984 Feb 10;223(4636):594–597. [PubMed]
  • Wiencke JK, Afzal V, Olivieri G, Wolff S. Evidence that the [3H]thymidine-induced adaptive response of human lymphocytes to subsequent doses of X-rays involves the induction of a chromosomal repair mechanism. Mutagenesis. 1986 Sep;1(5):375–380. [PubMed]
  • Wiencke JK. Nicotinamide deficiency in human lymphocytes prevents the [3H]thymidine-induced adaptive response for the repair of X-ray-induced chromosomal damage. Exp Cell Res. 1987 Aug;171(2):518–523. [PubMed]
  • Sankaranarayanan K, von Duyn A, Loos MJ, Natarajan AT. Adaptive response of human lymphocytes to low-level radiation from radioisotopes or X-rays. Mutat Res. 1989 Mar;211(1):7–12. [PubMed]
  • Shadley JD, Wolff S. Very low doses of X-rays can cause human lymphocytes to become less susceptible to ionizing radiation. Mutagenesis. 1987 Mar;2(2):95–96. [PubMed]
  • Wang ZQ, Saigusa S, Sasaki MS. Adaptive response to chromosome damage in cultured human lymphocytes primed with low doses of X-rays. Mutat Res. 1991 Jan;246(1):179–186. [PubMed]
  • Cai L, Liu SZ. Induction of cytogenetic adaptive response of somatic and germ cells in vivo and in vitro by low-dose X-irradiation. Int J Radiat Biol. 1990 Jul;58(1):187–194. [PubMed]
  • Vijayalaxmi, Burkart W. Resistance and cross-resistance to chromosome damage in human blood lymphocytes adapted to bleomycin. Mutat Res. 1989 Mar;211(1):1–5. [PubMed]
  • Kelsey KT, Memisoglu A, Frenkel D, Liber HL. Human lymphocytes exposed to low doses of X-rays are less susceptible to radiation-induced mutagenesis. Mutat Res. 1991 Aug;263(4):197–201. [PubMed]
  • Harley NH, Harley JH. Potential lung cancer risk from indoor radon exposure. CA Cancer J Clin. 1990 Sep-Oct;40(5):265–275. [PubMed]
  • Wolff S, Jostes R, Cross FT, Hui TE, Afzal V, Wiencke JK. Adaptive response of human lymphocytes for the repair of radon-induced chromosomal damage. Mutat Res. 1991 Sep-Oct;250(1-2):299–306. [PubMed]
  • Jostes RF, Hui TE, James AC, Cross FT, Schwartz JL, Rotmensch J, Atcher RW, Evans HH, Mencl J, Bakale G, et al. In vitro exposure of mammalian cells to radon: dosimetric considerations. Radiat Res. 1991 Aug;127(2):211–219. [PubMed]
  • Sasaki MS, Takatsuji T, Ejima Y, Kodama S, Kido C. Chromosome aberration frequency and radiation dose to lymphocytes by alpha-particles from internal deposit of Thorotrast. Radiat Environ Biophys. 1987;26(3):227–238. [PubMed]
  • Natarajan AT, Obe G. Molecular mechanisms involved in the production of chromosomal aberrations. I. Utilization of Neurospora endonuclease for the study of aberration production in G2 stage of the cell cycle. Mutat Res. 1978 Oct;52(1):137–149. [PubMed]
  • Natarajan AT, Obe G, van Zeeland AA, Palitti F, Meijers M, Verdegaal-Immerzeel EA. Molecular mechanisms involved in the production of chromosomal aberrations. II. Utilization of Neurospora endonuclease for the study of aberration production by X-rays in G1 and G2 stages of the cell cycle. Mutat Res. 1980 Feb;69(2):293–305. [PubMed]

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