Role of the ACE ID and MTHFR C677T polymorphisms in genetic susceptibility of migraine in a north Indian population

A Comprehensive Investigation into the Association Between Mthfr C677t, A1298c, and Ace I/D Variants and Risk of Migraine: an Updated Meta-Analysis of Genetic Association Studies with Trial Sequential Analysis and Meta-Regression

Many homeostatic genes are thought to play a role in the susceptibility to migraine, making it a highly complex neurovascular disease. In this meta-analysis, our primary objective was to evaluate whether or not MTHFR variants (such as C677T and A1289C) and ACE I/D were associated with an increased risk of migraine. Using a PRISMA-based systematic literature-review guideline, internet sources such as PubMed and Google Scholar were searched to identify the genes of interest and migraine risk. To pool the data, odds ratios with 95% confidence intervals were calculated utilizing different genetic models. Cochran's Q Test and I2 statistics were used to access heterogeneity, while Begg's and Egger's tests were used to identify publication bias. All tests were two-sided, and a p-value of < 0.05 was regarded as statistically significant. The present meta-analysis observed that the C677T variant is significantly associated with the increased risk of migraine (allele model: OR:1.19, CI [1.07-1.33], I2 = 78%) and its clinical subtype i.e., MA (allele model: OR: 1.26, CI [1.09-1.45], I2 = 80%) in the overall population. Concerning the ACE- I/D, it significantly increased the risk of overall migraine and both clinical subtypes after utilizing the dominant genetic models (OR: 1.14, CI [1.01-1.29], I2% = 32). Concerning the MTHFR A1289C, only the codominant model (HR vs HT) and recessive model significantly increased the risk of overall migraine. Therefore, the findings of the present meta-analysis showed that MTHFR-C677T is an important risk factor for migraine and its clinical subtype.

Comprehensive analysis of genes associated with migraine in the Indian population: a meta-analysis of genetic association studies with trial sequential analysis

Migraine is a complex disorder with multigenic inheritance and is characterized by the cardinal symptom of unilateral headache. Many genes are responsible for increasing the susceptibility of disease within different populations. Therefore, our primary aim in this review was to catalog the many genes that have been studied in India and after collecting the necessary information, we calculated a more precise risk relationship between an identified variation and migraine. The gene and its associated risk variant were discovered in the Indian population using a PRISMA-based systematic literature review guideline from online databases such as PubMed & Google Scholar. We constructed pooled odds ratios with 95% confidence intervals using multiple genetic models. Also, we looked for heterogeneity using Cochran's Q Test and the I2 statistic. Publication bias was analyzed using Begg's and Egger's tests. A p-value less than 0.05 was judged to be statistically significant for all tests. After a critical analysis, a total of 24 studies explored about 21 genes with 31 variants out of which only nine genes have been studied more than two times in the Indian population and thus were found eligible for the meta-analysis. It has been found, that the ACE-DD variant (allele model: OR: 1.37 [1.11-1.69], I2 = 0%/ fixed model), ESR1-PvuII (allele model: OR: 1.47 [1.24-1.74], I2 = 0%/ fixed model) significantly increases the risk of migraine in Indian population. Also, a protective role of the LRP1-rs11172113variant was observed for both migraine and its clinical subtype i.e., MA (allelic model: OR of 0.65 [0.50-0.83] I2 = 44% and allele: OR: 0.54 [0.37-0.78], I2 = 52%) respectively. Overall, the results of this meta-analysis indicated that the ACE-DD variant and the ESR1-PvuII were associated with an increased risk of migraine in the Indian community, while the LRP1-rs11172113 variant was associated with protection from migraine in this population.

Glucose-Related Traits and Risk of Migraine—A Potential Mechanism and Treatment Consideration

Migraine and glucose-related (glycaemic) traits (fasting glucose, fasting insulin, and type 2 diabetes) are common and complex comorbid disorders that cause major economic and social burdens on patients and their families. Studies on the relationship between migraine and glucose-related traits have yielded inconsistent results. The purpose of this review is to synthesise and discuss the information from the available literature on the relationship between fasting glucose, fasting insulin, and type 2 diabetes (T2D) with migraine. Publications on migraine and fasting glucose, migraine and fasting insulin, and migraine and T2D were identified from a PubMed and Google Scholar database search and reviewed for this article. Multiple publications have suggested that the comorbidity of migraine and glucose-related traits may have a similar complex pathogenic mechanism, including impaired glucose homeostasis, insulin resistance, reduced cerebrovascular reactivity, abnormal brain metabolism, shared genetic factors, neurotransmitters, and sex hormones. Furthermore, several studies have found a bi-directional link between migraine with insulin resistance and T2D. There is strong evidence for a biological association between migraine headache and glucose-related traits, and burgeoning evidence for shared genetic influences. Therefore, genetic research into these comorbid traits has the potential to identify new biomarkers and therapeutic targets and provide biological insight into their relationships. We encourage healthcare professionals to consider the co-occurrence of migraine with glucose-related traits in the evaluation and treatment of their patients.

Relation Between Methylenetetrahydrofolate Reductase Polymorphisms (C677T and A1298C) and Migraine Susceptibility

Migraine is a neurological disorder which impairs the patient's quality of life. Several association studies investigating the association between MTHFR gene C677T and A1298C polymorphisms and susceptibility to migraine were published. But the results were conflicting, so authors performed a meta-analysis of published case control studies to find out the exact association between MTHFR polymorphism and migraine susceptibility. Four databases were searched for suitable studies up to December, 2018. Odds ratios (OR) with 95% confidence intervals (CI) was calculated adopting additive, homozygote, co-dominant, dominant, and recessive genetic models. Results of MTHFR C677T polymorphism studies meta-analysis showed significant association with migraine risk using allele contrast, homozygote, dominant and recessive genetic models (T vs. C: OR = 1.18, 95% CI = 1.00-1.26, p = 0.05; TT vs. CC: OR = 1.24, 95% CI = 1.0-1.5, p = 0.04; CT vs. CC: OR = 1.08, 95% CI = 0.97-1.07, p = 0.25; TT + CT vs. CC: OR = 1.15, 95% CI = 1.0-1.29, p = 0.04; TT vs. CT + CC: OR = 1.97, 95% CI = 1.28-3.42, p = 0.002). However, results of MTHFR A1298 polymorphism studies meta-analysis did not show any association with migraine. Subgroup analysis based on ethnicity and migraine types i.e. migraine with aura (MA) and without aura (MO) were also performed. Results of present meta-analysis indicate overall association between MTHFR C677T polymorphism with migraine in total 24 studies, in Asian population and in MA cases but did not show any association with Caucasian population and MO cases.

Biomarkers in Migraine

Background

Disability from migraine has a profound impact on the world's economy. Research has been ongoing to identify biomarkers to aid in diagnosis and treatment.

Objective

The aim of this study was to highlight the purported diagnostic and therapeutic migraine biomarkers and their role in precision medicine.

Methods

A comprehensive literature search was conducted using PubMed, Google Scholar, and clinicaltrials.gov using keywords: "migraine" OR "headache" combined with "biomarkers" OR "marker." Other keywords included "serum," "cerebral spinal fluid," "inflammatory," and "neuroimaging."

Results

After a review of 88 papers, we find the literature supports numerous biomarkers in the diagnosis of migraine. Therapeutic biomarkers, while not as extensively published, highlight calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating peptide-38 (PACAP-38) as biomarkers with the most substantiated clinical relevance. Genetic markers mainly focusing on gene mutations with resultant biochemical alterations continue to be studied and show promise.

Conclusion

Although there are several proposed biomarkers for migraine, continued research is needed to substantiate their role in clinical practice.

Association of MTHFR gene polymorphisms with migraine in North Indian population

Polymorphisms in MTHFR gene are mostly associated with increased levels of homocysteine in the absence of dietary folate and are a risk factor for complex neurovascular diseases like migraine. The aim of present case-control study was to determine the association between MTHFR gene polymorphisms (C667T; rs 1801133, A1298C; rs 1801131) with migraine susceptibility. In total, 100 patients with migraine (23with MA and 77 with MO) and age-sex matched 100 healthy controls were included in this study from OPD of ESIC Medical College & Hospital, Faridabad. Genotyping was done by PCR-RFLP method. Genotypic and allelic frequencies were compared by SPSS 24 version. Genotypic results indicated a non-significant increase in frequencies of CT and TT in C667T SNP in migraine patients with control (52 and 10% vs. 42 and 7%: p > 0.05), but CC genotype in A1298C was found to be a risk factor in migraine patients than controls (30 vs. 17% respectively: p < 0.05). On comparing migraine subclasses, migraine with aura (MA) and without aura (MO) with control groups, the present study suggests that in MTHFR polymorphisms, the prevalence of 677CT genotype and T allele in C667T SNP influences susceptibility to MA (p < 0.05) but not to MO. Meanwhile, CC genotype in A1298C SNP could be a risk factor for migraine patients without aura (p < 0.05).

Association of ACE Gene I/D polymorphism with migraine in Kashmiri population

Introduction:

Migraine is a complex, recurrent headache disorder that is one of the most common complaints in neurology practice. The role of various genes in its pathogenesis is being studied. We did this study to see whether an association exists between ACE gene I/D polymorphism and migraine in our region.

Materials and Methods:

The study included 100 patients diagnosed with migraine and 121 healthy controls. The study subject were age and gender matched. The analysis was based on Polymerase Chain Reaction (PCR) and included following steps: DNA extraction from blood, PCR and Restriction Fragment Length Polymorphism (RFLP).

Results:

Out of 100 cases, 69 were females and 31 were males. Fifty-seven were having migraine without aura and 43 had migraine with aura. 45 of the cases had II polymorphism, 40 had ID polymorphism and 15 had DD polymorphism in ACE gene.

Conclusion:

We were not able to find a statistically significant association between ACE gene I/D polymorphism with migraine. The reason for difference in results between our study and other studies could be because of different ethnicity in study populations. So a continuous research is needed in this regard in order to find the genes and different polymorphism that increase the susceptibility of Kashmiri population to migraine.

Association between migraine and ACE gene (insertion/deletion) polymorphism: the BioBIM study

AIM

In the present case-control study, we investigated the correlation between the common ACE insertion/deletion (I/D) polymorphism and migraine.

MATERIALS & METHODS

Genotyping of the ACE I/D variant was performed in 502 Caucasian patients with migraine and 323 age-, sex- and race/ethnicity-matched healthy controls. We investigated associations between ACE genetic variants and sociodemographic and/or clinical features of migraineurs.

RESULTS

We found a significant association between ACE insertion/insertion (I/I) polymorphism and lower use of pharmacological prophylaxis in migraine patients with aura and in those with chronic migraine. Moreover, ACE I/I polymorphism was significantly more common in migraine patients with aura who had a negative family history of migraine.

CONCLUSION

Our data suggest that although the ACE I/D polymorphism is not a direct risk factor for migraine, the ACE I/I genotype may influence the clinical feature of this disease being associated with reduced use of prophylactic agents in patients with migraine with aura and in those with chronic migraine.

Migraine genetics: current findings and future lines of research

In the last two decades, migraine research has greatly advanced our current knowledge of the genetic contributions and the pathophysiology of this common and debilitating disorder. Nonetheless, this knowledge still needs to grow further and to translate into more effective treatments. To date, several genes involved in syndromic and monogenic forms of migraine have been identified, allowing the generation of animal models which have significantly contributed to current knowledge of the mechanisms underlying these rare forms of migraine. Common forms of migraine are instead posing a greater challenge, as they may most often stem from complex interactions between multiple common genetic variants, with environmental triggers. This paper reviews our current understanding of migraine genetics, moving from syndromic and monogenic forms to oligogenic/polygenic migraines most recently addressed with some success through genome-wide association studies. Methodological issues in study design and future perspectives opened by biomarker research will also be briefly addressed.

The renin-angiotensin system: a possible contributor to migraine pathogenesis and prophylaxis

The presence of a tissue-based renin-angiotensin system, independent of the systemic one, has been identified in several organs including the brain. Experimental models have suggested the involvement of the renin-angiotensin system in neurogenic inflammation, susceptibility to oxidative stress, endothelial dysfunction, and neuromodulation of nociceptive transmission, thus potentially contributing to the pathogenesis of migraine. Genetic factors that increase susceptibility to migraine may include angiotensin-converting enzyme polymorphism, although available data are controversial. Clinical studies have suggested that angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may be effective in migraine prophylaxis. However, further research should clarify whether the postulated preventive effect is attributable to a pharmacological action over and above the antihypertensive effect and should test their tolerability in subjects with normal blood pressure values. In patients with contraindications or not responding to conventional prophylactic drugs and in patients with comorbid arterial hypertension, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers may be used for migraine prophylaxis.

Investigation of MTHFR C677T gene polymorphism, biochemical and clinical parameters in Turkish migraine patients: association with allodynia and fatigue

We investigated whether there is any relationship between biochemical and clinical parameters of migraine and methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism, associated with the migraine subtypes, symptoms, and gender. A total of 150 migraine patients with and without aura (MA and MO) and 107 non-sufferers were included in the study. Biochemical and clinical parameters were measured and genetic analysis was performed. The MTFHR C677T genotype was significantly higher in the migraine group (p = 0.000). The CT genotype frequency of individuals with a family history of migraine was significantly higher (p = 0.025). This genotype frequency was higher in patients who suffer from compression, allodynia, fatigue, and sleeplessness (p = 0.027, 0.023, 0.006, and 0.05, respectively). Homocysteine and total cholesterol levels were significantly higher in the migraine group than the control group (p = 0.007 and 0.010, respectively). However, the other biochemical and clinical parameters did not differ from each other (p > 0.05), with only attack frequency being significantly higher in the MO group (p = 0.005). While the folate and HDL levels were significantly higher in females (p = 0.001 and 0.000, respectively), the homocysteine and triglyceride levels were significantly higher in males (p = 0.000 for each one). BMIs were significantly lower in the control than the migraine group (p = 0.021); however, an association between the C677T variant and BMI was not found (p = 0.787) in the migraine group. An association between the MTHFR C667T polymorphism and migraine susceptibility was found. Additional studies including genetic, clinic, and biochemical parameters should be conducted to better understand the disease.

Association of angiotensin I-converting enzyme gene insertion/deletion polymorphism with rheumatic heart disease in Indian population and meta-analysis

Rheumatic heart disease (RHD) is one of the most severe consequences of rheumatic fever. It has been suggested that angiotensin I-converting enzyme (ACE) may be involved in the increased valvular fibrosis and calcification in the pathogenesis of RHD. We conducted a case-control study to look for association of ACE I/D polymorphism with RHD in Indian population. The study incorporated 300 patients (170 males and 130 females) with RHD, and 200 controls (118 males and 82 females). We also subgrouped RHD patients into mitral valve lesion (MVL) and combined valve lesion (CVL). ACE I/D polymorphism was identified using polymerase chain reaction method. We also performed a meta-analysis of three published studies and the present study (636 RHD cases and 533 controls) to evaluate the association between the ACE I/D polymorphisms and RHD risk. A significant difference in ACE ID and DD genotypes distribution between RHD cases (OR = 1.62, 95% CI = 1.11-2.36 and OR = 2.08, 95% CI = 1.02-4.15, respectively) and corresponding controls was observed. On comparing the ACE genotypes of MVL and CVL subgroups with controls, ID and DD genotypes were also significantly associated with CVL (FDR Pcorr = 0.009, OR = 2.19 and FDR Pcorr = 0.014, OR = 3.29, respectively). Meta-analysis also suggested association of the ACE D allele (FDR Pcorr = 0.036, OR-1.22, 95% CI 1.02-1.45) with RHD. In conclusion, ACE ID and DD genotypes are associated with an increased risk of RHD, particularly CVL. This suggests that the ACE I/D gene polymorphism may play an important role in the pathogenesis of RHD.

Lack of association between the MTHFR C677T variant and migraine with aura in an older population: could selective survival play a role?

BACKGROUND

Several studies, but not all, of primarily middle-aged or younger adults have suggested that the common MTHFR C677T variant is a genetic risk factor for migraine with aura (MA). Here, we consider whether this variant is associated with MA risk in an older non-clinical population (AGES-Reykjavik cohort).

METHODS

Participants are a sub-sample ( N  = 1976) of subjects from the Reykjavik Study (RS; mean age 50) and its continuation, AGES-RS (mean age 76). We estimated the relative odds of MA in TT versus CC carriers using multinomial logistic regression. As both MA and the TT genotype may be linked with modestly reduced longevity, we performed a simple simulation to illustrate the effect that selective survival may have had on our observed gene-disease association.

RESULTS

TT versus CC carriers were at marginally reduced odds of MA (ORTT 0.55 (0.3-1.0), P  = 0.07), significantly for women (ORTT 0.45 (0.2-0.9), P  = 0.03). Assuming the 'true' (e.g. mid-life) effect of the TT genotype is ORTT 1.26, from a recent meta-analysis, our simulation suggested that if 25-year mortality had been (hypothetically) 13% higher in MA subjects with the TT versus CC genotype, the measured effect of the TT genotype on MA would have been attenuated to non-significance (e.g. ORTT 1.00). Our observed protective effect was consistent with the most extreme selective mortality scenario, in which essentially all of the previously reported increased mortality in MA subjects was (hypothetically) found in CT or TT carriers.

CONCLUSION

The MTHFR 677TT genotype was associated with marginally reduced risk of MA in our older population. Our simulation illustrated how even modest selective survival might obscure the apparent effect of a genetic or other risk factor in older populations. We speculate that some of the heterogeneity previously observed for this particular genetic variant may be due to age range differences in the studied populations.

Methylenetetrahydrofolate reductase gene polymorphisms as predictive and prognostic biomarkers in ovarian cancer risk

Early diagnosis and better prognosis of ovarian cancer is still a challenge. Besides environmental risk factors, genetic factors have established a role in pathogenesis of ovarian cancer.

METHODS

A case-control and a prospective study design conducted in 224 ovarian cancer patients and 432 controls in Chinese population. MTHFR C677T genotyping was done by PCR-RFLP.

RESULTS

Patients with ovarian cancer is associated with a higher less number of delivery and less frequent oral contraceptive use. When potential confounding factors adjusted logistic regression analysis between cases and controls were performed, significant association was obtained for 677T/T genotype and ovarian cancer (OR=3.13, 95% CI=1.59-5.72). Cox regression survival analysis showed individuals carrying T/T genotype had significantly increased HR for death in ovarian cancer patients (HR=2.86, 95% CI=1.27-7.93). In conclusion, we observed that the MTHFR C677T polymorphism is associated with the susceptibility and survival of ovarian cancer in Chinese population.

Methylenetetrahydrofolate reductase gene variant (MTHFR C677T) and migraine: a case control study and meta-analysis

Background

Migraine is a common disorder that often coexists with depression. While a functional polymorphism in methyleneterahydrofolate reductase gene (MTHFR C677T) has been implicated in depression; the evidence to support an association of MTHFR with migraine has been inconclusive. We aim to investigate the effect of this variant on propensity for migraine and to perform a systematic review and meta-analysis of studies of MTHFR and migraine to date.

Methods

Individuals with migraine (n = 447) were selected from the Depression Case Control (DeCC) study to investigate the association between migraine and MTHFR C677T single nucleotide polymorphism (SNP) rs1801133 using an additive model compared to non-migraineurs adjusting for depression status. A meta-analysis was performed and included 15 studies of MTHFR and migraine.

Results

MTHFR C677T polymorphism was associated with migraine with aura (MA) (OR 1.31, 95% CI 1.01-1.70, p = 0.039) that remained significant after adjusting for age, sex and depression status. A meta-analysis of 15 case-control studies showed that T allele homozygosity is significantly associated with MA (OR = 1.42; 95% CI, 1.10-1.82) and total migraine (OR = 1.37; 95% CI, 1.07-1.76), but not migraine without aura (OR = 1.16; 95% CI, 0.36-3.76). In studies of non-Caucasian population, the TT genotype was associated with total migraine (OR= 3.46; 95% CI, 1.22-9.82), whereas in studies of Caucasians this variant was associated with MA only (OR = 1.28; 95% CI, 1.002-1.63).

Conclusions

MTHFR C677T is associated with MA in individuals selected for depression study. A meta-analysis of 15 studies supports this association and demonstrated effects across ethnic groups.

Vascular gene polymorphisms (EDNRA -231 G>A and APOE HhaI) and risk for migraine

Migraine is a neurovascular disorder, and hence, any alteration in vascular endothelial function by either the endothelin system or the apolipoproteins may contribute to its pathophysiology. Thus, we investigated the role of EDNRA -231 G>A and APOE HhaI polymorphism for a possible association with migraine. Genotyping of 613 subjects consisting of 217 migraine subjects, 217 healthy controls (HC), and 179 subjects with tension-type headache was performed using the standard PCR-RFLP method. Data were analyzed by taking the Bonferroni-corrected p-values into account. We found significant difference in the frequency of EDNRA AA genotype between migraine subjects when compared with HC (p-value = 0.005; OR = 2.542; confidence interval [CI] = 1.329-4.863). A similar trend was shown by female migraine subjects at genotype and allele levels. The association of EDNRA -231 G>A polymorphism with migraine fit a recessive model (migraine vs. HC, p-value = 0.002; OR = 1.917; CI = 2.268-2.898). Female migraineurs without aura (MO) followed a similar trend. In the case of APOE HhaI polymorphism, E3E4 and E2E3 genotypes conferred risk when taken together in case of migraine versus HC (p-value = 0.005; OR = 2.715; CI = 1.342-5.490) and migraine with aura (MA) versus HC (p-value = 0.004; OR = 3.422; CI = 7.992). The risk was also seen after stratification on the basis of gender in female migraineurs (total migraine and MA). The interaction of EDNRA and APOE genotypes did not show further significance. The AA genotype and A allele of EDNRA -231 G>A polymorphism conferred risk for total migraine and MO. In APOE HhaI polymorphism, E3E4 and E2E3 conferred risk when taken together in total migraine and MA.

Evaluation of MTHFR677C>T polymorphism in prediction and prognosis of esophageal squamous cell carcinoma: a case-control study in a northern Indian population

Early diagnosis and better prognosis of esophageal squamous cell carcinoma (ESCC) is still a challenge. Besides environmental risk factors, nutritional deficiencies have an established role in pathogenesis of ESCC. Folate deficiency and functional polymorphisms in folate metabolizing genes such as methylene tetrahydrofolate reductase (MTHFR) 677C>T may have oncogenic role through disruption of normal DNA methylation pattern, synthesis, and impaired DNA repair. MTHFR677C>T or A222V (rs1801133) polymorphism has conflicting role in susceptibility to ESCC among different populations. Thus, we aimed to study the role of MTHFR677C>T polymorphism in susceptibility, survival, and interaction with environmental risk factors in ESCC patients from a northern Indian population. A case control study was performed in 208 ESCC incident cases (including 114 follow-up cases) and 223 healthy controls, and genotyping was done by PCR-RFLP. Our results show no significant association of MTHFR677C>T polymorphism with ESCC, tumor locations, or gender of subjects. However, we found a trend of decreased risk of ESCC due to interaction of MTHFR677CT genotype with smoking and alcohol intake. Kaplan Meier, and Cox regression survival analysis showed no prognostic impact of MTHFR677C>T polymorphism in ESCC patients. In conclusion, MTHFR677C>T polymorphism does not seem to have significant role either in susceptibility or survival of ESCC in a northern Indian population.

MTHFR 677C->T and ACE D/I polymorphisms and migraine attack frequency in women

Data on the association of the MTHFR 677C→T and ACE D/I polymorphisms with migraine severity, measured by attack frequency, are scarce. We performed an association study among 24 961 women participating in the Women's Health Study. Migraine, aura status and attack frequency were self-reported. Multinomial logistic regression was used to investigate the genotype-migraine association. Among the 3186 migraineurs with complete genotype and attack frequency data, 1270 reported migraine with aura (MA) (attack frequency 76 ≥ weekly; 219 monthly; 123 every other month; 852 fewer than six times/year) and 1916 migraine without aura (MoA) (attack frequency: 85 ≥ weekly; 414 monthly; 208 every other month; 1209 fewer than six times/year). The MTHFR 677TT genotype was associated with a reduced risk for MA, which only appeared for attacks fewer than six times/year (age-adjusted odds ratio 0.78; 95% confidence interval 0.61, 0.99). We did not find a specific pattern of association of the ACE D/I polymorphism with attack frequency for MA or MoA.

Investigation of TNFA 308G > A and TNFB 252G > A polymorphisms in genetic susceptibility to migraine

We aimed to look for the association of tumor necrosis factor (TNF) gene polymorphisms (TNFA 308G > A, and TNFB 252G > A) in genetic susceptibility to migraine. The pathogenesis of migraine involves many immune-mediated mechanisms in the vascular endothelium. TNF, being a potent immunomodulator and pro-inflammatory cytokine, is suggested to be involved in inflammatory reactions leading to migraine attacks. A total of 216 normotensive migraine patients, 160 tension type headache (TTH) patients and 216 healthy controls (HC) were recruited in the study. The genetic polymorphisms were investigated through SNP association analysis using a matched case control migraine population. Genotyping of TNFA 308G > A polymorphism and TNFB 252G > A was done using ARMS PCR and PCR-RFLP, respectively. A borderline association was observed in TNFA 308GA genotype in migraine patients versus HC (p = 0.043; OR = 1.763; 95% CI = 1.019-3.051). After sub-grouping migraine into migraine with aura (MA) or without aura, significant difference at genotypic (p = 0.015; OR = 2.293; 95% CI = 1.172-4.487) as well as allelic (p = 0.035; OR = 1.955; 95% CI = 1.047-3.651) level was evident. The difference was even more significant in female MA at genotypic (p = 0.006; OR = 2.901; 95% CI = 1.361-6.181) and allelic level (p = 0.017; OR = 2.318; 95% CI = 1.159-4.635) as well as for A allele carriers in MA [p value = 0.020; OR = 2.205 (1.132-4.295)] and female MA (p value = 0.008; OR = 2.741; CI = 1.297-5.792). No association of TNFB252G > A was observed in migraine patients or any subgroups. We did not find any association of TNFA or TNFB gene polymorphisms with TTH. In conclusion, the TNFA 308G > A polymorphism was found to be associated with MA, particularly in females, whereas we could not find any association of TNFB 252G > A polymorphism in genetic susceptibility to migraine on comparing the migraine patients with HC or TTH patients.

MTHFR 677C>T and ACE D/I polymorphisms in migraine: a systematic review and meta-analysis

BACKGROUND

Data on the association between the MTHFR 677C>T and ACE D/I polymorphisms and migraine including aura status are conflicting.

OBJECTIVE

The objective of this study is to perform a systematic review and meta-analysis on this topic.

METHODS

We searched for studies published until March 2009 using electronic databases (MEDLINE, EMBASE, Science Citation Index) and reference lists of studies and reviews on the topic. Assessment for eligibility of studies and extraction of data was performed by 2 independent investigators. For each study we calculated the odds ratios (OR) and 95% confidence intervals (CI) assuming additive, dominant, and recessive genetic models. We then calculated pooled ORs and 95% CIs.

RESULTS

Thirteen studies investigated the association between the MTHFR 677C>T polymorphism and migraine. The TT genotype was associated with an increased risk for any migraine, which only appeared for migraine with aura (pooled OR = 1.48, 95% CI 1.02-2.13), but not for migraine without aura. Nine studies investigated the association of the ACE D/I polymorphism with migraine. The II genotype was associated with a reduced risk for migraine with aura (pooled OR = 0.71, 95% CI 0.55-0.93) and migraine without aura (pooled OR = 0.84, 95% CI 0.70-0.99). Results for both variants were driven by studies in non-Caucasian populations. Results among Caucasians did not suggest an association. Extractable data did not allow investigation of gene-gene interactions.

CONCLUSIONS

The MTHFR 677TT genotype is associated with an increased risk for migraine with aura, while the ACE II genotype is protective against both migraine with and without aura. Results for both variants appeared only among non-Caucasian populations. There was no association among Caucasians.

Relationship between genetic polymorphisms of angiotensin-converting enzyme and methylenetetrahydrofolate reductase as risk factors for type 2 diabetes in Tunisian patients

BACKGROUND/AIMS

The role of methylenetetrahydrofolate reductase (MTHFR) and angiotensin-converting enzyme (ACE) gene polymorphisms as being risk factors for diabetes is still controversial. The aim was to investigate the distribution of ACE and MTHFR genotypes as well as to evaluate the role of plasmatic total homocysteine levels (tHcy) and ACE activity in Tunisian patients with type 2 diabetes mellitus (T2DM).

DESIGN AND METHODS

115 T2DM patients compared to 116 healthy volunteers.

RESULTS

The ACE I/D polymorphism was significantly associated with diabetes (p<0.0001). The DD genotype and D allele were more frequent in patients compared to control group [DD: OR=4.93; p<0.0001; 95 % CI: 2.71-8.97; D: OR=3.08, 95% CI: 2.09-4.51 p<0.0001]. MTHFR allele and genotype frequencies did not differ between patients and controls. The susceptibility to diabetes in individuals with genotypes DD+vTT was 13.39 and in the individuals with DD+CT was 6.57 times that of the controls. However, individuals with genotypes ID+CC or II+CT have a protective effect against diabetes. The DD and TT genotypes were associated with significantly higher ACE activity and tHcy levels in diabetics.

CONCLUSION

Our data suggest that ACE ID polymorphism may act synergistically with MTHFR C677T polymorphism to assess diabetes risk.