The data was analysed using Statistica software 6.0 (Statsoft).
The mean values of TD were normalized using its square root and
analysed by an ANOVA. The effect of hydrogen peroxide exposure
on the number of signals detected by FISH for major rDNA
genes was analysed using a Mann–Whitney U test. The correlation
between
√
TD and the number of signals was studied using
Spearman’s correlation coefficient.