| General populations of Japan (Tonomura et al. 1983) |
Scenario
To obtain a basic chromosome aberration data
in healthy general Japanese populations referable to effects of low doses
of ionizing radiation and environmental mutagens, a large scale chromosome
aberration analysis was conducted covering varying ages in both sexes who
have not experienced diagnostic X-ray examinations at least within the
last 2 years. A total of 96 blood samples were collected from adult individuals
in different age categories from 20 years old to 60 years old (age in ±
1 or 2 years) and a group of new born infants. The 2-day (50 h) lymphocyte
cultures were established and chromosome aberrations were studied in Giemsa-stained
preparations. All unbroken metaphase spreads were photographed under microscope
and chromosome aberration analysis and visual karyotyping were performed
on photoprints.
| Reference |
|
Tonomura, A., Kishi, K. and Saito, F. (1983): Types and frequencies of chromosome aberrations in peripheral lymphocytes of general populations. In, Ishihara, T. and Sasaki, M. S., eds., “Radiation-induced Chromosome Damage in Man”, Alan R. Liss, Inc., New York, pp. 605-616. |
| Chromosome aberration analysis |
| Age group | Sex | No. of | Chromatid-type aberrations | Chromosome-type aberrations | Aneuploid cells | |||||||||||
| Male | Female | cells | ctg | ictg | ctb | ictb | cte | dic | ring | mono | tr | ex frag | >;2n | |||
| Newborns | 11 | 12 | 15,325 | 1,122 | 81 | 102 | 31 | 9 | 0 | 0 | 4 | 1 | 14 | 37 | ||
| 20 yr | 5 | 8 | 12,495 | 774 | 78 | 86 | 10 | 12 | 9 | 1 | 4 | 3 | 11 | 36 | ||
| 30 yr | 10 | 10 | 20,322 | 1,116 | 122 | 159 | 58 | 17 | 17 | 1 | 9 | 5 | 26 | 83 | ||
| 40 yr | 12 | 10 | 21,560 | 1,471 | 165 | 136 | 65 | 17 | 25 | 1 | 18 | 6 | 24 | 106 | ||
| 50 yr | 10 | 11 | 18,546 | 1,160 | 146 | 125 | 45 | 15 | 26 | 4 | 10 | 6 | 20 | 168 | ||
| 60 yr | 10 | 10 | 19,544 | 1,356 | 113 | 159 | 67 | 8 | 19 | 7 | 15 | 5 | 34 | 222 | ||
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Graphic representations: |
