The Children of Atomic Bomb Survivors A Genetic Study (1991) / Chapter Skim
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Cytogenetic Study of the Offspring of Atomic Bomb Survivors, Hiroshima and Nagasaki
Cytogenetic Study of the Offspring of Atomic Bomb Survivors, Hiroshima and Nagasaki
Pages 344-362
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From page 344... ...
, and has been continued to the present time In conjunction with the ongoing mortality study and biochemical genetics survey on the Fat progeny (RERF Research Protocol 1975~. The main objective of the present study is to evaluate the radiation sensitivity of human germ-cell chromosomes by measuring the frequency of children with chromosome changes in structure or number induced by radiation in the germ cells of exposed parents.
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From page 345... ...
When family studies were performed on probands with structural rearrangements, high resolution banding techniques (Yunis et al. 1978; Pal and Thomas 1980)
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From page 346... ...
The exposed group was further divided into three categories by parental exposure status; i.e., children born to parents in which only the father was exposed, only the mother was exposed, or both parents were exposed. Since efforts were made to collect as many cases as possible in the exposed group, the number of children per parental couple is considerably higher in the exposed group than in the controls (Table 1~; 1.4 children per couple (or 8,322 in 5,823)
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From page 347... ...
The majority of the abnormalities was due to sex chromosome aneuploidy, mostly XW and XXY in males and XXX in females, which constituted 757O of the total sex THE CHILDREN OF ATOMIC BOMB SURVIVORS 347
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From page 348... ...
O~ O O C~ ~ O tt, :r: X~ ~ O O C~ ~ ~ 't e~ ~ _ ~ THE CHILDREN OF ATOMIC BOMB SURVIVORS 348
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From page 349... ...
in the Hiroshima controls. A family study revealed that the abnormality was identified as a de novo mutant since both parents showed the normal karyotype.
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From page 351... ...
None have been detected so far in Nagasaki. The gametic mutation rates on structural rearrangements derived from the combined data were estimated as 1.72 x 10-4 in the exposed group, and 1.40 x 10-4 in the controls, respectively.
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From page 352... ...
Yet none of these differences are significantly different. The data from the two cities were combined, regardless of parental radiation exposure, and each of the frequencies was compared with that of corresponding abnormalities in the cytogenetic surveys on 56,952 consecutive liveborn infants (Hook and THE CHILDREN OF ATOMIC BOMB SURVIVORS 352
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From page 353... ...
4 Discussion As mentioned previously, the main objective of this study was to demonstrate whether there is any measurable ~ncrease in the frequency of children with chromosome abnormalities that might be associated with A-bomb radiation exposure of parental germ-cell chromosomes. This cytogenetic evaluation was conducted by comparing the frequencies of children born to A-bomb survivors with chromosome abnormalities, especially structural rearrangements, with children born to nonexposed parents.
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From page 354... ...
Extensive cytogenetic surveys on consecutive liveborn infants, undertaken as international collaborative studies in several European and North American countries, have provided very useful and relevant information on the natural incidence of various types of constitutional chromosome abnormalities in the human population (Sergovich et al. 1969; Lubs and Ruddle 1970; Friedrich and Nielsen 1973; Jacobs et al.
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From page 355... ...
Finally, when the new A-bomb radiation dosimetry system (DS86) becomes available for estimating the dose for individual survivors, the present data will be reanalyzed to determine the relationship between the frequency of chromosome abnormalities observed in children as a function of parental gonadal dose.
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From page 356... ...
. The gametic mutation rates on structural rearrangements derived from the combined data in Tables 8 and 9 were estimated as 0.98 X 10-4 in the exposed, and 0.98 X 10-4 in the controls, respectively.
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From page 357... ...
The frequency of chromosome abnormalities detected in consecutive newborn studies - differences between studies - results by sex and by severity of phenotypic involvement. In: Hook EB, Porter IH (eds)
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From page 358... ...
Radiation Effects Research Foundation, Hiroshima, 1983 2nd US-Japan joint Worksh Reassessment of atomic bomb radiation dosimetry in Hiroshima and Nagasaki. Radiation Effects Research Foundation, Hiroshima, 1984 Walzer S
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