Slyskova, J., Lorenzo, Y., Karlsen, A., Carlsen, M. H., Novosadova, V., Blomhoff, R., Vodicka, P., Collins, A. R. Both genetic and dietary factors underlie individual differences in DNA damage levels and DNA repair capacity. DNA Repair, 16(2014): 66-73, 2014. doi: 10.1016/j.dnarep.2014.01.016. ISSN 1568-7864.
The interplay between dietary habits and individual genetic make-up is assumed to influence risk of cancer, via modulation of DNA integrity. Our aim was to characterize internal and external factors that underlie inter-individual variability in DNA damage and repair and to identify dietary habits beneficial for maintaining DNA integrity.
Habitual diet was estimated in 340 healthy individuals using a food frequency questionnaire and biomarkers of antioxidant status were quantified in fasting blood samples. Markers of DNA integrity were represented by DNA strand breaks, oxidized purines, oxidized pyrimidines and a sum of all three as total DNA damage. DNA repair was characterized by genetic variants and functional activities of base and nucleotide excision repair pathways.
Sex, fruit-based food consumption and XPG genotype were factors significantly associated with the level of DNA damage. DNA damage was higher in women (p = 0.035). Fruit consumption was negatively associated with the number of all measured DNA lesions, and this effect was mediated mostly by β-cryptoxanthin and β-tocopherol (p < 0.05). XPG1104His homozygotes appeared more vulnerable to DNA damage accumulation (p = 0.001). Sex and individual antioxidants were also associated with DNA repair capacity; both the base and nucleotide excision repairs were lower in women and the latter increased with higher plasma levels of ascorbic acid and α-carotene (p < 0.05).
We have determined genetic and dietary factors that modulate DNA integrity. We propose that the positive health effect of fruit intake is partially mediated via DNA damage suppression and a simultaneous increase in DNA repair capacity.