Subgroup analyses suggested that the T allele of the NOS3 +894G>T variant increased the risk for migraine among non-Caucasians, which was driven by associations for MA (co-dominant model TT vs. GG: pooled OR = 2.10; 95% CI 1.14–3.88), as shown in Table 3 and Fig 4). Here, NOS3 is linked to migraine disorder.