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.