Knol MJ, Loehrer EA, Wen KX, et al. - Researchers examined how migraine genetic variants are associated with cerebral blood flow (CBF). From the population-based Rotterdam Study, 4,665 participants (mean age 65.0 ± 10.9 years, 55.6% women) were assessed for cross-sectional area (mm²), flow velocity (mm/s), and blood flow (mL/min) in both carotids and the basilar artery using 2-dimensional phase-contrast magnetic resonance imaging. A separate analysis of 43 previously identified migraine variants and calculation of a genetic risk score (GRS) were done. Using linear regression models adjusted for age, sex, and total brain volume, the association with CBF was assessed. Higher flow velocity and smaller cross-sectional area in the carotids were evident in correlation with the rs67338227 risk allele. They observed migraine risk variants to be enriched for flow in the basilar artery (λ = 2.39). These findings suggest a complex relationship of genetic migraine risk with alterations in cerebral hemodynamics.