Ling YH, et al. - Given the reported association of many single nucleotide polymorphisms (SNPs) with migraine susceptibility, researchers here examined the relations of preidentified migraine susceptibility loci in Taiwanese with migraine endophenotypes or subtypes, including chronic migraine and allodynia. They tested the correlation between six SNPs (TRPM8 rs10166942, LRP1 rs1172113, DLG2 rs655484, GFRA1 rs3781545, UPP2 rs7565931, and GPR39 rs10803531) and migraine endophenotypes, including chronic migraine and allodynia among 1,904 patients (mean age 37.5 ± 12.2 years old, female ratio: 77.7%). Of the total participants, 1,077 were recruited in the discovery cohort and 827 in the replication cohort. In both discovery and replication cohorts and combined samples, patients carrying TRPM8 rs10166942 T allele more frequently had chronic migraine than non-T allele carriers. In addition, more allodynic symptoms were reported among T allele carriers vs non-T allele carriers. Findings suggest a possible contributory role of TRPM8 in the pathogenesis of chronic migraine. However, this study provides no evidence supporting allodynia as a link between them.