We show that the number of abasic sites is significantly increased when the 3-methyladenine DNA glycosylase (Mag): AP endonuclease (Apn1) ratio is increased and that spontaneous frame shift mutation is considerably elevated when either Mag, or Mag plus Apn1, expression is elevated.
It is interesting to note that the number of dominant mutations was considerably smaller in the primary tumour than the metastatic lesion.
PolZeta appears to be involved in the repair of at least some of these DSBs, as the frequency of HO-induced base substitution mutations was considerably lower in an isogenic rev3 Δ strain (Holbeck and Strathern 1997).
Thus, the probability of transformants having no untargeted mutations is considerably increased both by using high-fidelity Taq polymerases and by minimizing the size of the PCR fragment.
The assay detected ≥ 10% mutated mtDNA in each case, and for some mutations, the detection threshold was considerably lower (Table S1).
However, transmission of TALEN-induced mutations to the next generation was considerably lower at the ADH1 locus (69% for ZFNs vs. 12% for TALENs).
The frequency of typical mutations, such as albino phenotype, was considerably higher in our library than in previously reported soybean mutant populations [ 40, 41].
However, the actual number of mutations between these two haplotypes was considerably less at 23 (equating to 4.7% divergence) suggesting that there are a number missing links within the network and that it is poorly resolved.
The mutation frequency determined in this investigation was considerably lower than reported in the general literature; nevertheless, two other studies documented comparably lower p53 mutation frequencies of 8 and 12% (also at codon 245) (Casson et al, 1991; Gonzalez et al, 1997).
Turning to the residues giving the largest effects, Pro39, Val40, and Gly41, we found that the rate reduction due to mutation of each of these residues was considerably smaller in the D38E background than with the WT Asp general base, suggesting that each of these residues plays a role in positioning the general base for catalysis.
