Methionine Synthase Reductase-A66G and -C524T Single Nucleotide Polymorphisms and Prostate Cancer: A Case-Control Trial

Impact of Methionine Synthase Reductase Polymorphisms in Chronic Myeloid Leukemia Patients

Introduction： Metabolism methionine and of folate play a vital function in cellular methylation reactions, DNA synthesis and epigenetic process.However, polymorphisms of methionine have received much attention in recent medical genetics research. Objectives: To ascertain whether the common polymorphisms of the MTRR (Methionine Synthase Reductase) A66G gene could play a role in affecting susceptibility to Chronic Myeloid Leukemia (CML) in Sudanese individuals. Methods: In a case-controlled study, we extracted and analyzed DNA from 200 CML patients and 100 healthy control subjects by the PCR-RFLP method. Results: We found no significant difference in age orgender between the patient group and controls. The MTRR A66G genotypes were distributed based on the Hardy-Weinberg equilibrium (p > 0.05). The variation of MTRR A66G was less significantly frequent in cases with CML (68.35%) than in controls (87%) (OR = 0.146, 95% CI = 0.162−0.662, p < 0.002). Additionally, AG and GG genotypes and G allele were reducing the CML risk (Odds ratio [OR] = 0.365; 95% CI [0.179−0.746]; p = 0.006; OR = 0.292; 95% CI [0.145−0.590]; p = 0.001 and OR = 0.146; 95% CI [0.162−0.662]; p = 0.002 and OR = 2.0; 95% CI [1.3853−2.817]; respectively, (p = 0.000)). Conclusions: Our data demonstrated that heterozygous and homozygous mutant genotypes of MTRR polymorphisms were associated with decreased risk of developing CML in the Sudanese population.

Riboflavin intake, MTRR genetic polymorphism (rs1532268) and gastric cancer risk in a Korean population: a case-control study

The vitamin B group, including riboflavin, plays paramount roles in one-carbon metabolism (OCM), and disorders related to this pathway have been linked to cancer development. The variants of genes encoding OCM enzymes and the insufficiency of B vitamins could contribute to carcinogenesis. Very few observational studies have revealed a relationship between riboflavin and gastric cancer (GC), especially under conditions of modified genetic factors. We carried out a study examining the association of riboflavin intake and its interaction with MTRR (rs1532268) genetic variants with GC risk among 756 controls and 377 cases. The OR and 95 % CI were evaluated using unconditional logistic regression models. We observed protective effects of riboflavin intake against GC, particularly in the female subgroup (OR = 0·52, 95 % CI 0·28, 0·97, Ptrend = 0·031). In the MTRR (rs1532268) genotypes analysis, the dominant model showed that the effects of riboflavin differed between the CC and CT + TT genotypes. Compared with CC carriers, low riboflavin intake in T+ carriers was significantly associated with a 93 % higher GC risk (OR = 1·93, 95 % CI 1·09, 3·42, Pinteraction = 0·037). In general, higher riboflavin intake might help reduce the risk of GC in both CC and TC + TT carriers, particularly the T+ carriers, with marginal significance (OR = 0·54, 95 % CI 0·28, 1·02, Pinteraction = 0·037). Our study indicates a protective effect of riboflavin intake against GC. Those who carry at least one minor allele and have low riboflavin intake could modify this association to increase GC risk in the Korean population.

Genetic and molecular biology of autism spectrum disorder among Middle East population: a review

BACKGROUND

Autism spectrum disorder (ASD) is a neurodevelopmental disease, characterized by impaired social communication, executive dysfunction, and abnormal perceptual processing. It is more frequent among males. All of these clinical manifestations are associated with atypical neural development. Various genetic and environmental risk factors are involved in the etiology of autism. Genetic assessment is essential for the early detection and intervention which can improve social communications and reduce abnormal behaviors. Although, there is a noticeable ASD incidence in Middle East countries, there is still a lack of knowledge about the genetic and molecular biology of ASD among this population to introduce efficient diagnostic and prognostic methods.

MAIN BODY

In the present review, we have summarized all of the genes which have been associated with ASD progression among Middle East population. We have also categorized the reported genes based on their cell and molecular functions.

CONCLUSIONS

This review clarifies the genetic and molecular biology of ASD among Middle East population and paves the way of introducing an efficient population based panel of genetic markers for the early detection and management of ASD in Middle East countries.

Genetic polymorphisms in folate-metabolizing genes associated with gastric cancer prognosis in northwest China subjects

Influence of folate metabolism has long been studied in cancer and copies evidences have suggested that the key genes involved were correlated with GC risk and prognosis. However, their genetically association and contribution for GC prognosis are still elusive. To evaluate the effect of folate metabolism related genes polymorphisms on the prognosis of gastric cancer (GC), the genotype of seven single nucleotide polymorphisms (SNPs) of three genes were selected and genotyped in a cohort of 664 GC patients, including genes of Methylenetetrahydrofolate reductase (MTHFR), Methionine synthase reductase (MTRR), and Methionine synthase (MTR). Kaplan-Meier Curve, long-rank tests and multivariate Cox proportional hazard model were used for prognosis analysis. The results demonstrated that TT or CT/TT genotypes of SNP rs1532268 in MTRR gene coding region are significantly associated with a poorer overall survival (OS) when compared with CC genotype (HR=2.340, 95% CI: 1.240-4.414, p=0.009; or HR=1.502, 95% CI: 1.083-2.085, p=0.015, respectively). Furthermore, comparing to that of the CC genotype, the detrimental effect of rs1532268 TT genotype was also evident in the special subgroups of GC patients, especially in patients with BMI<24 and H. pylori infection. Moreover, significant association between increased relapse and TT genotype of rs1532268 was also observed in patients who are females, BMI<24 and without chemotherapy. In addition, the joint analysis demonstrated that integration of rs1532268 genotypes and BMI, H. pylori infection status, clinical stage and tumor site may significantly improve the predictive abilities for predicting OS of GC patients. In conclusion, it suggested that the MTRR rs1532268 polymorphism is significantly associated with clinical outcomes of GC patients, especially in those with lower BMI (BMI<24) or positive H. pylori infection status, which warrants further validation. And the polymorphism of MTRR rs1532268 may be a potential prognostic factor for GC patients.

Association of genetic and epigenetic variants in one-carbon metabolism gene with folate treatment response in hyperhomocysteinaemia

BACKGROUND

Folate supplementation treatment is the first-line therapy in hyperhomocysteinaemia (HHcy). Up to 40% of HHcy patients do not benefit from folate therapy. Genetic and epigenetic factors of one-carbon metabolism (1-CM) might be identified as a predictor of folate supplementation treatment response. In the present study, we attempt to identify whether genetic and epigenetic factors might predict folate treatment response.

METHODS

A total of 230 patients with HHcy were involved in this prospective cohort study. Differences between baseline concentrations and concentrations obtained at 90 days of treatment were calculated to evaluate the treatment response. General linear models and Pearson correlation was used to explore associations among single-nucleotide polymorphisms (SNPs), DNA methylation, and folate treatment response. Finally, mediation analysis was performed to investigate whether DNA methylation of MTRR mediates the association between SNPs and treatment response.

RESULTS

MTHFD rs1950902 and MTRR rs162036, rs1801394 was associated with the folate treatment response (P = 0.000, 0.048, and 0.043, respectively). CBS and CBS_2 DNA methylation was significantly associated with folate treatment response (P = 0.0009 and < 0.001). DNA methylation of MTHFR, MTR, and MTRR was also significantly associated with folate treatment response (P < 0.001). DNA methylation of MTRR and MTRR_1 mediated 40.71% and 40.47% of the effect of rs1801394 on folate treatment response, respectively.

CONCLUSIONS

Our results indicated that the 1-CM gene SNPs and DNA methylation was associated with folate treatment response and can be further evaluated relationship between SNPs and DNA methylation in 1-CM with treatment response in a larger sample.