OGG1 rs1052133 Polymorphism and Genetic Susceptibility to Chronic Myelogenous Leukaemia

Association between polymorphisms of the DNA repair genes RAD51 and OGG1 and risk of cardiovascular disease

Cardiovascular disease (CVD) is one of the leading causes of mortality worldwide, and multiple single‑nucleotide polymorphisms of DNA repair genes have been found to be associated with CVD. The aim of the present study was to assess the effects of the genetic variants of RAD51 recombinase (RAD51) and 8‑oxoguanine DNA glycosylase (OGG1) on CVD through genotyping and statistical analysis. Regardless of whether there is a significant association or not, the genotyping data on these two polymorphisms are valuable, because there is limited availability of it in certain populations. A total of 240 blood samples were analyzed and genotyped using TaqMan genotyping; 120 were obtained from cases with a history of CVD, and 120 from cases with no history of CVD. A questionnaire was administered to gather information on age, demographics, sex and clinical features, and confirmation was carried out using medical records. The results of the present study confirmed that the polymorphism rs1052133 in OGG1 had no significant association with CVD. On the other hand, the polymorphism rs1801321 in RAD51 exhibited a significant association with CVD. Collectively, the results of the present study revealed that the polymorphism rs1801321 in RAD51 exhibited a significant association with CVD, however a larger sample size to confirm the present findings, may allow for the early identification of CVD and may aid in the decision‑making process concerning treatments for CVD.

DNA repair pathways as guardians of the genome: Therapeutic potential and possible prognostic role in hematologic neoplasms

DNA repair pathways, which are also identified as guardians of the genome, protect cells from frequent damage that can lead to DNA breaks. The most deleterious types of damage are double-strand breaks (DSBs), which are repaired by homologous recombination (HR) and non-homologous end joining (NHEJ). Single strand breaks (SSBs) can be corrected through base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR). Failure to restore DNA lesions or inappropriately repaired DNA damage culminates in genomic instability and changes in the regulation of cellular functions. Intriguingly, particular mutations and translocations are accompanied by special types of leukemia. Besides, expression patterns of certain repair genes are altered in different hematologic malignancies. Moreover, analysis of mutations in key mediators of DNA damage repair (DDR) pathways, as well as investigation of their expression and function, may provide us with emerging biomarkers of response/resistance to treatment. Therefore, defective DDR pathways can offer a rational starting point for developing DNA repair-targeted drugs. In this review, we address genetic alterations and gene/protein expression changes, as well as provide an overview of DNA repair pathways.

MTHFR, XRCC1 and OGG1 genetic polymorphisms in breast cancer: a case-control study in a population from North Sardinia

BACKGROUND

Despite conflicting results, considerable evidence suggests the association between single nucleotide polymorphisms in MTHFR, XRCC1 and OGG1 genes and, risk of developing breast cancer. Here a case-control study is reported, including 135 breat cancer patients and 112 healthy women, all representative of Northern Sardinian population.

METHODS

Polymerase chain reaction/restriction fragment length polymorphism method was used to determine the genotypes of five polymorphisms: MTHFR C677T (rs1801133) and A1298C (rs1801131), XRCC1 Arg194Trp (rs1799782) and Arg399Gln (rs25487) and OGG1 Ser326Cys (rs1052133). Allelic, genotypic and haplotype association analyses with disease risk and clinicopathological parameters were performed.

RESULTS

A nominally significant association with breast cancer risk was observed for MTHFR C677T polymorphism heterozygous genotype in the codominant model (OR: 0.57, 95% CI: 0.32-1.00, p = 0.049) and for Cys/Cys genotype of the OGG1 Ser326Cys polymorphism in the recessive model (OR: 0.23, 95% CI: 0.05-1.11, p = 0.0465). No significant differences were found at genotype-level for A1298C polymorphism of the MTHFR gene and Arg194Trp and Arg399Gln of the XRCC1 gene. Furthermore, the OGG1 and XRCC1 rs25487 polymorphisms were nominally associated with PgR, Her2 status and with sporadic breast cancer, respectively.

CONCLUSIONS

Based on genetic characteristics of individuals included in this study, results suggest that MTHFR CT and OGG1 Cys/Cys genotypes have a protective effect that may have an influence on breast cancer risk in a representative Northern Sardinian population.