Types and frequencies of human chromosome aberrations induced by x-rays

Journal Article · Thu Jun 01 04:00:00 EDT 1961 · Proceedings of the National Academy of Sciences of the United States of America

DOI:https://doi.org/10.1073/pnas.47.6.830· OSTI ID:4068055

Chu, E. H. Y.; Giles, N. H.; Passano, K.

Qualitative and quantitative analyses were made of x-ray induced chromosome aberrations in human euploid cells grown in culture. Two major categories of aberrations, chromatid and chromosome, are present in irradiated cells. Chromatid types constitute the only aberrations in cells observed shortly after irradiation; chromosome types begin to appear and finally completely replace the former in successively later post-irradiation periods. A general decrease in radiosensitivity occurs in conjunction with this temporal shift in the appearance of aberration types. Quantitative results for both the chromatid and chromosome aberration types indicate that, in general, terminal deletions increase linearly with dose, whereas exchanges exhibit an exponential relationship. The frequency of spontaneous aberrations, which are almost exclusively one-hit chromatid types, is on the average 0.1 aberrations per cell in all post irradiation periods. The induced frequency at the most radiosensitive period of the cell, which follows the period during which the chromosomes become effectively double, is 0.02 aberrations per cell per roentgen. Such cells are about 5 times more sensitive than cells at interphase when chromosomes are effectively single. The coefficient of chromosome aberration production by x-rays in human somatic cells is shown to be not significantly different from that in certain plant cells. This conclusion supports the view that the mechanics of chromosome aberration production by radiation are similar in both plant and mammalian cells. However, this result cannot be taken to mean that radiosensitivity, in terms of genetic damage, mutation production, and cell killing, is necessarily the same in plant and mammalian, especially human, cells. (auth)

• Research Organization: Yale Univ., New Haven
• Sponsoring Organization: USDOE
• NSA Number: NSA-15-022123
• OSTI ID: 4068055
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 6 Vol. 47; ISSN 0027-8424
• Publisher: National Academy of Sciences, Washington, DC (United States)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANIMAL CELLS
BIOLOGY AND MEDICINE
CHROMOSOMES
CYTOLOGY
GENETICS
MAN
MUTATIONS
PLANT CELLS
RADIATION EFFECTS
RADIOSENSITIVITY
X RADIATION