Genomics and Applied Biology 2016, Vol.7, No.2, 1-7
6
MN increases in lymphocytes depending on age and gender (Kutbay, 2001; Fenech, 2007).
SCE is a cytological indicator of segment change among the homologous areas of DNA replication products as a
result of DNA breakage and recombination. According to a paper submitted by Tucker et al. in 1993, the
interpretation that SCE frequency is an indication of genotoxic effect is based either on doubling of SCE number
compared with the control group or a statistical increase in any dose (p<0.05) (Rodriguez-Mercado et al., 2003).
SCE increased in patients with cervical cancer, nasopharyngeal carcinoma, prostate, ovarian carcinoma, acute
leukemia and Chronic lymphocytic leukemia
(CLL). It was observed in studies on breast cancer that SCE
increased in patients and patients with nonmalignant fibroadenoma. In another study, SCE and CA also increased
in patients with hereditary breast cancers and their first degree relatives. Perhaps, chromosomal instability will be
a guide in patients with hereditary breast cancer (Çefle, 2006).
In a study which Fenech conducted in 1993, it was shown that MN increased in all patients depending on dosage
in different patient groups that received RT treatment. In the same study, periodic measurements were taken after a
12-month RT and increases of 91.6% were observed 3 months later, 72% 6 months later and 57% 12 months later
(Fenech, 1993). Buckton obtained similar results in patients with ankylosing spondylitis (Buckton, 1983). In our
study, a significant increase was observed in SCE frequencies in RT-b (p=0.008) and RT-c (p=0.005) groups when
compared with the control group. When RT-b and RT-c groups were compared with RT-a group in terms of SCE,
again significant increases were determined in terms of SCE. No difference was observed in SCE when RT-b and
RT-c groups were compared between themselves. In conclusion, our study is in parallel with other studies in terms
of SCE.
4 Conclusion
Increasing MN and SCE frequencies following radiotherapy is an expected situation. Decrease in MN frequency
at 3-month after the completion of RT suggests that expected repair continues. Persistent SCE at the same period
suggests that recovery in SCE has not completed yet and a longer period of time is needed.
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