Association Between Multiple Single Nucleotide Polymorphisms in Folate Metabolism Pathway and Breast Cancer Risk in Georgian Women: A Case-Control Study

Background

The folate metabolism pathway plays an integral part in DNA synthesis, methylation, and repair. Methylenetetrahydrofolate reductase (MTHFR) and methylenetetrahydrofolate dehydrogenase (MTHFD1) are both enzymes that are involved in this pathway, and the single nucleotide polymorphisms (SNPs) in genes coding for them have modulatory effects on DNA expression. This study aimed to investigate the relationship between MTHFR C677T (rs1801133) and MTHFD1 G1958A (rs2236225) polymorphisms and the risk of developing breast cancer in Georgian women.

Methods

A case-control study was performed examining the MTHFR C677T and MTHFD1 G1958A SNP in breast cancer-confirmed cases and healthy matched controls. Real time-polymerase chain reaction (PCR) was used to genotype SNPs. The case individuals' pathology reports were obtained following surgeries for cancer characteristic data. Statistical analysis was performed to investigate the significance of the acquired data.

Results

Statistical analysis of MTHFR C677T SNP revealed that the CT genotype increased the risk of breast cancer by 2.17 folds in the over-dominant model. Statistical analysis of MTHFD1 G1958A SNP showed that the GA genotype increased the risk of breast cancer by 4.12 folds in the codominant model and 2.41 folds in the over-dominant model. No statistically significant link was found between genotypes and lymph node status, however, patients with the CT genotype had higher percentages of proliferative activity.

Conclusions

Breast cancer seems to have a statistically significant association with the CT genotype in MTHFR C677T and the GA genotype in MTHFD1 G1958A in Georgian women.

IL-10 Polymorphism and Breast Cancer Risk in Georgian Women: A Case-Control Study

Background  Interleukin-10 (IL-10) is a cytokine with a vast variety of functions, but its role in cancer development and progression is not yet clear. It is involved in two of the hallmarks of cancer: vascularization and immune modulation. IL-10 inhibits angiogenesis and hence is antitumorigenic. But it also can suppress the immune system and be tumorigenic. Objective  Evaluating the role of IL-10 (-1082 A/G) gene promoter single-nucleotide polymorphism (SNP) in breast cancer susceptibility and progression in Georgian women. Methods  A case-control study was performed on a total of 128 women, with 64 of them being histologically confirmed to have breast cancer and 64 healthy controls. SNP genotyping was performed with TaqMan assay with real-time polymerase chain reaction. And pathology report, containing proliferative activity and breast cancer hormonal status, was obtained after surgery of the case individuals. Statistical analysis was done to investigate the significance of data obtained from genotyping and histology reports. Results  Statistical analysis revealed that the difference in frequency of genotypes was not statistically significant between cases and controls (chi-square = 0.5812, p  = 0.7478). The comparison of proliferative activity of cases with AA genotypes and AG/GG genotypes showed no statistical difference ( t  = 0.2575, p  = 0.7980). Although when put into a plot (box and whiskers), patients with AG/GG genotype have outliers with very high proliferative activity. Conclusion  This study shows that -1082 A/G SNP in the promoter region of the IL-10 gene is not associated with breast cancer risk in Georgian women.

DNA methylation status of interspersed repetitive sequences in patients with migraine

OBJECTIVE

To analyse the methylation status of the Long Interspersed Nuclear Element-1 (LINE-1) and Short Interspersed Nuclear Element Alu (Alu) of peripheral blood mononuclear cells (PBMCs) from patients with migraine compared with healthy control subjects.

METHODS

This case-control study recruited patients with migraine without aura and age-matched healthy control subjects. PBMCs were purified from peripheral blood samples. Methylation levels and patterns of LINE-1 and Alu sequences were evaluated using combined bisulfite restriction analysis-interspersed repetitive sequences polymerase chain reaction.

RESULTS

A total of 84 patients with migraine and 82 age-matched healthy controls were enrolled in the study. High levels of unmethylated cytosines in both the LINE-1 and Alu repetitive elements were observed in the migraine group compared with the control subjects. In addition, a significant difference was detected in the methylation level of LINE-1 between TT and CC genotype groups of the methylenetetrahydrofolate reductase gene.

CONCLUSIONS

These results suggest that analysis of epigenetic biomarkers in PBMCs may help to identify patients at a higher risk of migraine development.

Public attitudes towards the genetic testing in Georgia

The aim of this study is to assess attitudes towards genetic testing in Georgian public. We used a Likert-scale written questionnaire. The survey was completed by 480 respondents. A majority of respondents (75.3%) curious about predictive genetic testing and 40.6% of participants preferred to be tested only for disorders that are treatable or preventable. Approximately 65% of the participants would like to test their newborn children for late-onset disorders and undergo preconception carrier screening (73%). In addition, the majority (59%) of our respondents were not worried that genetic testing would further stigmatize people with disabilities. These results indicate that the respondents surveyed in our study may have placed particularly high importance on the availability of genetic testing and greatly valued access to genomic information.

Methylenetetrahydrofolate Reductase (MTHFR) C677T and A1298C Polymorphisms in Georgian Females with Hypothyroidism

The aim of this study was to investigate the frequency of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms in Georgian females with hypothyroidism. Thirty-four patients and 29 healthy individuals were recruited in this study. Polymerase chain reaction-restriction fragment length polymorphism analyses were used for genotyping of MTHFR polymorphisms. The results of this study suggest that the MTHFR C677T variant was significantly associated with hypothyroidism. In addition, in individuals with T allele risk of hypothyroidism significantly increased. Combination of CT/AA genotypes was more prevalent in the hypothyroid patients than in the control group. Thus, C677T polymorphism could be a possible genetic factor contributing to the pathophysiology of hypothyroidism, possibly through hyperhomocysteinemia.