In fact, migraine prevalence correlates with the evidence of positive selection and the frequency of the T allele: DAF at rs10166942 shows a positive correlation with migraine prevalence (Pearson’s rho = 0.61), although the correlation is not significant (P-value = 0.11) perhaps because we have comparable genetic [34] and migraine [57] data for only eight countries (S7 Table). Here, CD55 is linked to migraine disorder.