H. Kusakabe et al., DETECTION OF NEOCARZINOSTATIN-INDUCED TRANSLOCATIONS IN HUMAN SPERM CHROMOSOMES USING FLUORESCENCE IN-SITU HYBRIDIZATION OF CHROMOSOME-2, Mutation research. Genetic toxicology testing, 369(1-2), 1996, pp. 51-58
Mature sperm and late spermatid are known to be sensitive stages to cl
astogens in mammalian spermatogenesis. Certain types of chromosomal da
mage induced in these stages will pass to successive generations as he
ritable translocations. In the present study, we employed whole chromo
some 2 painting with the fluorescence in situ hybridization (FISH) tec
hnique to detect the chemically induced translocations in human sperm.
Mature human sperm were treated in vitro with an antitumor drug, neoc
arzinostatin (NCS), and fertilized in vitro with golden hamster oocyte
s. Sperm pronuclear chromosome slides were prepared at the first cleav
age metaphase. To compare the characteristics of translocations betwee
n somatic and germ cells, human lymphocytes in peripheral blood treate
d with NCS in vitro were analyzed at first round metaphase after PHA-s
timulation. From the analysis of translocations by whole chromosome 2
painting, frequencies of the haploid genomic translocations (F-hG) wer
e predicted for both sperm and lymphocytes. At 1.0 mu g/ml, the actual
percentages of sperm and lymphocytes with chromosome 2 translocations
were almost identical (11.9% and 12.0%). At the same dose, however, t
he F-hG of the sperm (1.15) was considerably higher than that of the l
ymphocytes (0.58), indicating that complex translocations having two o
r more rearranged sites were induced by NCS more frequently in sperm t
han in lymphocytes.