Association analysis of serotonin transporter gene polymorphism among the South-Indian migraineurs.

Background: Migraine is a multifactorial neurological disorder characterized by frequent moderate to severe intensity headaches. The genetic variations in synaptic and post-receptor signalling proteins have direct effect on the process of serotonergic neurotransmission. Methods: We aimed to investigate the genetic association of serotonin transporter (SERT) 5-hydroxytryptamine transporter-linked promoter region (5-HTTLPR) polymorphism and migraine risk in South-Indian population. A total of 304 subjects with migraine including with aura (MA) and without aura (MO) and 308 controls were included in the present study. The single nucleotide polymorphism (SNP) was detected using polymerase chain reaction (PCR) and confirmed by deoxyribonucleic acid (DNA) sequencing. Results: The genotyping analysis revealed insignificant relationship with migraine subjects when compared with controls (P > 0.05). The minor 'S' allele showed no association with odds ratio (OR) = 1.23 [95% confidence interval (CI): 0.90-1.66], heterozygote with OR = 1.18 (95% CI: 0.82-1.69), and homozygote with OR = 1.51 (95% CI: 0.52-4.35). Conclusion: Further clinical studies are required to validate the results of SERT 5-HTTLPR promoter polymorphism in diverse ethnic descents especially in Asian populations.