- 5, In December 1955 the Advisory Committee on Biology and
Medicine approved a number of recommendations made by its ad hoc
genetics committee,
These recommendations are being put into
effect as rapidly as possible, and the following developments can
already be reported:
a, The mouse genetics program at Oak Ridge
National Laboratory is being expanded to investigate
the rates at which mutations are induced by lower
-levels of radiation exposure, While earlier investiga-
tions have been made at 1,000, 600, and 300 roentgens,
attention will now center on exposures of 150 roentgens,
and possibly 75 roentgens,
b, The number of studies in the fields of human
genetics and medical genetics increased from two to
four during the quarter, and additional projects may
quelify for support,
Tnese studies deal with the
rates of spontaneous mutation and the frequencies of
unfavorable genes already in the population.
Such
information is necessary for extrapolation from
orservations on experimental species to predicted
effects of radiation on humens,
ec. Genetics is sharing in the broad benefits
expected from the new ability to grow cultures of
human tissue for medical experimentation,
Methods
for studying the genetic effects of radiation on
human cells in tissue culture, still in the planning
stage a few months ago, have been perfected to the
extent that quantitative results are already being
obtained. By these methods it will be possible for the
first time to make direct comparisons between responses
of human cells and cells of other species under
standardized experimental conditions, and thus make
knowledge gained from animal experimentation much more
directiy applicable to man,
croc
DOE ARCHIVE
6, There is little likelihood that scientists will ever be
able to determine with extreme precision the genetically harmful
effects of low doses of radiation on human populations, even
retrospectively,
The uncertainty is inherent because mutations of
"natural" origin and those caused by otner factors are not
identifiably different from mutations induced by radiation.
Greater kmowledge will nevertheless provide a sounder basis for
regulating the exposure of human populations to radiation as
CO)
the use of atomic energy expands,