DNA damage, repair and mutations

Studies on electron beam induced DNA damage and repair kinetics in lymphocytes by alkaline comet assay

Background: Exposure to ionizing radiation is known to induce oxidative stress followed by damage to critical biomolecules like lipids, proteins and DNA through radiolysis of cellular water. Since radiation has been widely used as an important tool in therapy of cancer, the detailed investigation regarding the DNA damage and repair kinetics would help to predict the radiation sensitivity of cel...

OGG1 DNA Repair Gene Polymorphism As a Biomarker of Oxidative and Genotoxic DNA Damage

Background: Single nucleotide polymorphisms in 8-oxoguanine DNA glycosylase-1 (OGG1) gene modulates DNA repair capacity and functions as one of the first lines of protective mechanisms against 8-hydroxy-2’-deoxyguanosine (8-OHdG) mutagenicity. OGG1-Cys326 gene polymorphism may decrease DNA repair function, causing oxidative stress due to higher oxidative DNA damage. The main purpose of this stu...

Radiosensitivity and Repair Kinetics of Gamma-Irradiated Leukocytes from Sporadic Prostate Cancer Patients and Healthy Individuals Assessed by Alkaline Comet Assay

Background: Impaired DNA repair mechanism is one of the main causes of tumor genesis. Study of intrinsic radiosensitivity of cancer patients in a non-target tissue (e.g. peripheral blood) might show the extent of DNA repair deficiency of cells in affected individuals and might be used a predictor of cancer predisposition. Methods: Initial radiation-induced DNA damage (ratio of Tail DNA/Head DN...

Origin and Role of DNA Damage in Varicocele

The DNA damage checkpoint pathways exert multiple controls on the efficiency and outcome of the repair of a double-stranded DNA gap.

A DNA gap repair assay was used to determine the effect of mutations in the DNA damage checkpoint system on the efficiency and outcome (crossover/non-crossover) of recombinational DNA repair. In Saccharomyces cerevisiae gap repair is largely achieved by homologous recombination. As a result the plasmid either integrates into the chromosome (indicative of a crossover outcome) or remains extrachr...

Topical DNA oligonucleotide therapy reduces UV-induced mutations and photocarcinogenesis in hairless mice.

UV-induced DNA damage gives rise to mutations and skin cancer. We have previously reported that treatment of skin cells in vitro with thymidine dinucleotide (pTT) activates p53 and increases the ability of cells to repair subsequent UV-induced DNA damage by enhancing endogenous DNA repair capacity. Here we show that topical pTT pretreatment enhances the rate of DNA photoproduct removal, decreas...