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The D2 receptor Nco I allele: Absence of allelic association with migraine with aura

To the Editor: The identification of two chromosomal loci responsible for familial hemiplegic migraine has provided new insight into the genetic basis of migraine.1,2 However, these families appear to be rare, and the genes involved in the common forms of migraine are still unidentified. Based on pedigree data and pharmacologic studies, Russel concluded that there is a different genetic basis for migraine with aura (MWA) and migraine without aura(MO).3

In a recent article, Peroutka et al. reported on an overrepresentation of the "C" allele of the D2 dopamine receptor (DRD2) Nco I polymorphism among MWA patients.4 The frequency of this allele among their MWA cases was 0.81 as compared with 0.70 in MO and 0.71 in controls.4 Based on clinical, pharmacologic, and neuroanatomic evidence suggesting the involvement of the dopaminergic system during migraine attacks, they hypothesized that the DRD2 Nco I polymorphism may …